Method and apparatus for delivering an implant without bias to a left atrial appendage

ABSTRACT

An implant delivery system, comprising: an implantable device comprising a plurality of supports extending between a proximal end and a distal end, the supports being moveable between a collapsed configuration and an expanded configuration, a proximal guide tube at the proximal end of the supports extending toward the distal end, and a distal guide tube at the distal end of the supports extending toward the proximal end, wherein the proximal and distal guide tubes are telescoping and become further engaged as the supports move from the collapsed to the expanded configuration.

CROSS-REFERENCE TO RELATED U.S. APPLICATIONS

This application is a continuation of U.S. Ser. No. 13/436,700, filedMar. 30, 2012, which is a continuation of U.S. Ser. No. 11/607,253,filed Dec. 1, 2006, now abandoned, which claims the benefit of priorityfrom U.S. Provisional No. 60/741,111, filed Dec. 1, 2005, which isincorporated by reference, herein.

BACKGROUND

Embolic stroke is the nation's third leading killer for adults, and is amajor cause of disability. There are over 700,000 strokes per year inthe United States alone. Of these, roughly 100,000 are hemorrhagic, and600,000 are ischemic (either due to vessel narrowing or to embolism).The most common cause of embolic stroke emanating from the heart isthrombus formation due to atrial fibrillation. Approximately 80,000strokes per year are attributable to atrial fibrillation. Atrialfibrillation is an arrhythmia of the heart that results in a rapid andchaotic heartbeat that produces lower cardiac output and irregular andturbulent blood flow in the vascular system. There are over five millionpeople worldwide with atrial fibrillation, with about four hundredthousand new cases reported each year. Atrial fibrillation is associatedwith a 500 percent greater risk of stroke due to the condition. Apatient with atrial fibrillation typically has a significantly decreasedquality of life due, in part, to the fear of a stroke, and thepharmaceutical regimen necessary to reduce that risk.

For patients who develop atrial thrombus from atrial fibrillation, theclot normally occurs in the left atrial appendage (LAA) of the heart.The LAA is a cavity which looks like a small finger or windsock andwhich is connected to the lateral wall of the left atrium between themitral valve and the root of the left pulmonary vein. The LAA normallycontracts with the rest of the left atrium during a normal heart cycle,thus keeping blood from becoming stagnant therein, but often fails tocontract with any vigor in patients experiencing atrial fibrillation dueto the discoordinate electrical signals associated with atrialfibrillation. As a result, thrombus formation is predisposed to form inthe stagnant blood within the LAA.

Blackshear and Odell have reported that of the 1288 patients withnon-rheumatic atrial fibrillation involved in their study, 221 (17%) hadthrombus detected in the left atrium of the heart. Blackshear J L, OdellJ A., Appendage Obliteration to Reduce Stroke in Cardiac SurgicalPatients With Atrial Fibrillation. Ann Thorac. Surg., 1996. 61(2):755-9.Of the patients with atrial thrombus, 201 (91%) had the atrial thrombuslocated within the left atrial appendage. The foregoing suggests thatthe elimination or containment of thrombus formed within the LAA ofpatients with atrial fibrillation would significantly reduce theincidence of stroke in those patients.

Pharmacological therapies for stroke prevention such as oral or systemicadministration of warfarin or the like have been inadequate due toserious side effects of the medications and lack of patient compliancein taking the medication. Invasive surgical or thorascopic techniqueshave been used to obliterate the LAA, however, many patients are notsuitable candidates for such surgical procedures due to a compromisedcondition or having previously undergone cardiac surgery. In addition,the perceived risks of even a thorascopic surgical procedure oftenoutweigh the potential benefits. See Blackshear and Odell, above. Seealso Lindsay B D., Obliteration of the Left Atrial Appendage: A ConceptWorth Testing, Ann Thorac. Surg., 1996.61(2): 515.

During surgical procedures, such as mitral valve repair, thrombus in theleft atrial appendage may leave the LAA and enter the blood stream of apatient. The thrombus in the blood stream of the patient can causeembolic stroke. There are known techniques for closing off the LAA sothat thrombus cannot enter the patient's blood stream. For example,surgeons have used staples or sutures to close the orifice of the LAA,such that the closed off LAA surrounds the thrombus. Unfortunately,using staples or sutures to close off the LAA may not completely closethe orifice of the LAA. Thus, thrombus may leave the LAA and enter thepatient's blood stream, even though the LAA is closed with staples orsutures. Additionally, closing the orifice of the LAA by using staplesor sutures may result in discontinuities, such as folds or creases, inthe endocardial surface facing the left atrium. Unfortunately, bloodclots may form in these discontinuities and can enter the patient'sblood stream, thereby causing health problems. Moreover, it is difficultto place sutures at the orifice of the LAA and may result in a residualappendage. For example, an epicardial approach to ligate sutures canresult in a residual appendage. Similarly, thrombus may form in theresidual appendage and enter the patient's blood stream causing healthproblems.

Despite the various efforts in the prior art, there remains a need for aminimally invasive method and associated devices for reducing the riskof thrombus formation in the left atrial appendage. Various implantabledevices and methods of delivery have been previously described. However,some delivery devices can have limited flexibility and can provideoff-axis loading that creates moment arms and bending bias. Moment armsand bending bias can cause the implant to “jump” or move within the leftatrial appendage when it is detached from the implant delivery system.Therefore, it would be advantageous for a left atrial appendageimplantation to system to avoid moment arms and bending bias such thatwhen the implant is released it remains in the position it had whencoupled to the delivery system.

SUMMARY OF THE INVENTION

There is provided in accordance with one embodiment of the presentinvention a system and method for minimizing, reducing, substantiallyeliminating, and/or eliminating implantation bias during delivery of animplant. The system includes an implant with a distal guide tube, anactuation shaft, and a concentrically attachable disconnect mount. Inone embodiment the implant is configured to contain emboli with a leftatrial appendage of a heart of a patient. The implantable device has aproximal and distal end with a plurality of supports and is moveablebetween a collapsed and an expanded configuration. The distal guide tubeat the distal end of the supports extends toward the proximal end of theimplant. The actuation shaft extends through the proximal end of theimplantable device and is removeably engageable with the distal guidetube. The disconnect mount is releasably engageable with the proximalend of the implant and is concentrically attachable to the proximal endof the implant. In one embodiment, the implant is self-expandable. Inanother embodiment, the implant is collapsed by engaging the actuationshaft with the distal guide tube while applying a relatively proximalforce to the proximal end of the implant with the disconnect mount.

In one embodiment of the present invention, an implant delivery systemincludes an implantable device, a proximal guide tube, and a distalguide tube. The implantable device has a plurality of supports extendingbetween a proximal end and a distal end. The supports are moveablebetween a collapsed configuration and an expanded configuration.

In one embodiment, the proximal guide tube is located at the proximalend of the supports and extends toward the distal end of the device. Thedistal guide tube is located at the distal end of the supports andextends toward the proximal end of the device. The proximal and distalguide tubes are telescoping and become further engaged as the supportsmove from the collapsed to the expanded configuration.

In another embodiment of the present invention, an implant deliverysystem includes an implantable device, an actuation shaft, and adisconnect mount. In some embodiments, the implant delivery systemfurther comprises a distal guide tube. The implantable device has aproximal end, a distal end, and a plurality of supports extendingtherebetween. The implantable device is moveable between a collapsedconfiguration and an expanded configuration.

In one embodiment, the distal guide tube, when provided, is located atthe distal end of the supports and extends toward the proximal end ofthe device. The actuation shaft is extendable through the proximal endof the implantable device and is removeably engageable with the distalguide tube. The disconnect mount is releasably engageable with theproximal end of the implantable device. The disconnect mount isconcentrically attachable to the proximal end of the implantable device.

In some embodiments, the implantable device is self-expanding. In otherembodiments, the implantable device is collapsed by engaging theactuation shaft with the distal guide tube while applying a relativelyproximal force to the proximal end of the implantable device with thedisconnect mount.

In yet another embodiment of the present invention, a method ofactuating an implantable device with a concentric force includesproviding an implantable device, applying a concentric force, andapplying a distal force. The implantable device has a proximal end, adistal end, and a plurality of supports extending therebetween. Theimplantable device is configured to expand from a reduced-diameterconfiguration to an expanded-diameter configuration. In one embodiment,the concentric force is applied to the proximal end. In otherembodiments, the distal force is applied to the distal end.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a view of a heart and its left atrial appendage;

FIG. 2 is a block diagram representing a simplified implant deliverysystem in accordance with one embodiment of the present invention;

FIG. 2A is a schematic view of one embodiment of the delivery system ofFIG. 2;

FIG. 3A is a side elevational view of the distal end of an embodiment ofan implant delivery system;

FIG. 3B is a side elevational view of the distal end of anotherembodiment of an implant delivery system;

FIG. 4A is a side elevational view of the distal end of the implantdelivery system shown in FIG. 3A with a radially-reduced implant;

FIG. 4B is a side elevational view of the distal end of the implantdelivery system shown in FIG. 4A with a radially-expanded implant;

FIG. 4C is a side elevational view of the distal end of an implantdelivery system shown in FIG. 4B with a released radially-expandedimplant;

FIG. 5A is a side elevational view of the distal end of the implantdelivery system shown in FIG. 3B with a radially-reduced implant;

FIG. 5B is a side elevational view of the distal end of the implantdelivery system shown in FIG. 5A with a radially-expanded implant;

FIG. 5C is a side elevational view of the distal end of an implantdelivery system shown in FIG. 5B with a released radially-expandedimplant;

FIG. 6 is a schematic view of a deployment system delivering animplantable containment device to the left atrial appendage;

FIG. 7 is a perspective view of a support structure for a containmentdevice in accordance with a further embodiment of the present invention;

FIG. 7A is a side elevational view of the device of FIG. 7;

FIG. 7B is an end view taken along the line 7B-7B of FIG. 7A;

FIGS. 8 and 9 are side elevational schematic representations of partialand complete barrier layers of the containment device of FIG. 7;

FIG. 10 is a side elevational schematic view of an alternate containmentdevice in accordance with another embodiment of the present invention;

FIG. 11 is a schematic view of a deployment system in accordance withone embodiment of the present invention;

FIG. 11A is an enlarged detail view of the deployment system of FIG. 11,showing a releasable lock in an engaged configuration;

FIG. 11B is an enlarged detail view as in FIG. 11A, with a core axiallyretracted to release the implant;

FIG. 12A is a perspective view of a flexible guide tube for use in theconfigurations of FIG. 11 and/or FIG. 14;

FIG. 12B is a schematic view of a flexible guide tube for use inembodiments of the configurations of FIG. 11;

FIG. 13A is a schematic view of an implant with concentric slideableguide tubes in a radially-reduced state in accordance with oneembodiment of the present invention;

FIG. 13B is a schematic view of the implant with concentric slideableguide tubes of FIG. 13A in a radially-expanded state;

FIG. 14 is a schematic view of an alternate deployment system inaccordance with one embodiment of the present invention;

FIG. 15A illustrates a schematic cross-sectional view through the distalend of a retrieval catheter having a containment device removablyconnected thereto in accordance with one embodiment of the presentinvention;

FIG. 15B is a perspective view of an embodiment of a single layer petalconfiguration of a portion of a retrieval catheter in accordance withone embodiment of the present invention;

FIG. 15C is a schematic cross-sectional view of the system illustratedin FIG. 15A, with the containment device axially elongated and radiallyreduced;

FIG. 15D is a cross-sectional schematic view as in FIG. 15C, with thecontainment device drawn part way into the retrieval catheter;

FIG. 15E is a schematic view as in FIG. 15D, with the containment deviceand delivery catheter drawn into a transseptal sheath;

FIG. 16A is a schematic cross-sectional view of a distal portion of anadjustable implant deployment system, in accordance with anotherembodiment;

FIG. 16B is a schematic partial sectional view of an assemblyincorporating quick-disconnect functionality of the assembly in FIG.16A;

FIGS. 17A-C are schematic cross-sectional views of an implant releaseand recapture mechanism having an internal lock tube, in accordance withanother embodiment;

FIGS. 18A-C are schematic cross-sectional views of another implantrelease and recapture mechanism having an internal lock tube, inaccordance with another embodiment;

FIGS. 19A-C are schematic cross-sectional views of an implant releaseand recapture mechanism of an implant deployment system having anexternal lock tube, in accordance with another embodiment;

FIGS. 20A-C are schematic cross-sectional views of another implantrelease and recapture mechanism having an external lock tube, inaccordance with another embodiment;

FIGS. 21A-C are schematic cross-sectional views of an embodiment of animplant release and recapture mechanism having a threaded portion of animplant actuation shaft, in accordance with another embodiment;

FIGS. 21D-E are cross-sectional views of another embodiment of animplant release mechanism;

FIG. 21F is a cross-section view of another embodiment of an implantrelease mechanism;

FIG. 22 is a schematic view of a delivery system in accordance with oneembodiment of the present invention;

FIG. 22A is a cross-sectional view of an implant delivery system asshown in FIG. 22, taken along line 22A-22A;

FIG. 23 is a partial cross-sectional view of the distal end of adeployment system constructed in accordance with one embodiment of thepresent invention;

FIG. 24 is a partial cross-sectional view of an axially moveable coreused in the system of FIG. 22;

FIG. 24A is a cross-sectional view of the axially moveable core of FIG.24 taken along line 24A-24A;

FIG. 25 is a schematic of an embodiment of a flexible catheter systemconstructed in accordance with one embodiment of the present invention;

FIG. 25A is a close up of an embodiment of a puzzle lock profileconstructed in accordance with one embodiment of the present invention;

FIG. 25B is a perspective view of a tube with the puzzle lock profile ofFIG. 25A; and

FIG. 25C is a close up of the puzzle lock profile of FIG. 25B.

DETAILED DESCRIPTION OF CERTAIN PREFERRED EMBODIMENTS

FIG. 1 illustrates a sectional view of a heart 5 and its left atrialappendage (LAA) 10. An implant 100 is provided at least partially withinthe LAA 10. The terms “implant”, “occlusion device” or “containmentdevice” are broad terms intended to have their ordinary meaning. Inaddition, these terms are intended to refer to devices that are insertedinto the body. Such devices may include a membrane, barrier and/orcover, or may omit these portions. Embodiments of the invention may alsobe used to treat other bodily openings, lumen and cavities, besides theLAA 10. For example, in some embodiments, the methods, devices andsystems described herein are used to treat any heart opening or defect,such as a patent foramen ovale (PFO), an atrial septal defect (ASD), aventricular septal defect (VSD), a patent ductus arteriosus (PDA), ananeurysm and/or an aortico-pulmonary window.

In various embodiments, an implant 100 can be delivered in a number ofways, e.g., using conventional transthoracic surgical, minimallyinvasive, or port access approaches. Delivery can be made or done inconjunction with surgical procedures as well. In one embodiment, theimplant 100 is used in conjunction with various surgical heartprocedures related to the heart (e.g., mitral valve repair) or surgicalprocedures in the region surrounding the heart. The delivery system canbe used to locate and deploy the implant 100 in order to prevent thepassage of embolic material from the LAA 10, such that thrombus remainscontained in the LAA 10. Thrombus remains contained in the LAA 100because the implant 100 inhibits thrombus within the LAA 10 from passingthrough the orifice of the LAA 10 and into the patient's blood stream.Additionally, the deployed implant 100 located in the LAA 10 can providea smooth, non-thrombogenic surface facing the left atrium. In oneembodiment, the smooth, non-thrombogenic surface facing the left atriumwill not promote blood clots to form proximate to the LAA 10. Access tothe heart may be provided by surgical procedures in order to deploy theimplant 100 in the LAA 10. That is, the implant 100 can be deployed asan adjunct to surgical procedures. Various methods for accessing the LAA10 and delivering an implant 100 to the LAA 10 are disclosed in U.S.application Ser. No. 11/003,696, filed Dec. 3, 2004, published as U.S.Publication No. 2005-0177182 A1, which is incorporated by referenceherein.

A. Implant Delivery System

FIG. 2 illustrates a block diagram of an implant delivery system 50. Theimplant delivery system 50 includes an implant 100, an implant releaseand recapture mechanism 200, a catheter system 300 and a deploymenthandle 400. In some embodiments, the implant release and recapturemechanism 200 is the distal portion of the catheter system 300 and thedeployment handle 400 is the proximal portion of the catheter system300. The implant release and recapture mechanism 200 generally couplesthe implant 100 to the catheter system 300. The deployment handle 400generally provides all the user controls and actuators of the implantdelivery system 50.

FIG. 2A illustrates one embodiment of the implant delivery system 50 ofFIG. 2. The implant delivery system 50 includes an implant release andrecapture mechanism 200 that is flexible and without bias. In thismanner, when the implant 100 is released from the delivery system 50,the implant 100 maintains the position and orientation it had whencoupled to the delivery system 50, and does not spring, jump, or move,as described above.

FIG. 3A illustrates one example of an implant 100 (schematically shown)coupled to a catheter system 300 with an implant release and recapturemechanism 200. In the illustrated embodiment, the implant release andrecapture mechanism 200 is relatively stiff and extends over a releasemechanism length 201. The implant release and recapture mechanism 200includes an implant actuation shaft 334 and a tether line 210. Theimplant 100 is generally self-expandable and is held in areduced-diameter configuration by pushing against the distal end of theinside of the implant 100 while pulling on the implant's proximal end.For example, the implant actuation shaft 334 pushes against the implantdistal end while the tether line 210 is held in tension to maintain theimplant 100 in a reduced-diameter configuration. To expand the implant,tension on the tether line 210 is reduced and/or the implant actuationshaft 334 is moved proximally.

However, the implant actuation shaft 334 and tether line 210 can havelimited flexibility and can provide off-axis loading that creates momentarms and bending bias. Deployment of the implant 100 in the confines ofthe heart 5 (not illustrated here) may require bending of the implantrelease and recapture mechanism 200, a catheter system 300, butstiffness along a release mechanism length 201 reduces flexibility andcreates moment arm and bending bias.

FIG. 3B illustrates another embodiment of an implant 100 coupled to acatheter system 300 with an implant release and recapture mechanism 200.In the illustrated embodiment, the implant release and recapturemechanism 200 is relatively stiff and extends over a release mechanismlength 202. The implant release and recapture mechanism 200 and thecatheter system 300 are flexible and can be manipulated in order toaccess the LAA 10. When device stiffness or rigidity along a releasemechanism length 202 is shorter than a release mechanism length 201, thedevice has increased flexibility and shorter moment arms, resulting inless bending bias.

FIGS. 4A-C illustrate the implant release sequence of the implant 100with the implant release and recapture mechanism 200 of FIG. 3A. FIG. 4Aillustrates an example of an implant 100, an implant release andrecapture mechanism 200, and a catheter system 300 where the implantrelease and recapture mechanism 200 is relatively stiff and extends overa release mechanism length 201. FIG. 4B illustrates a catheter system300 using an implant actuation shaft 334 and a tether line 210, whichare used as components within the implant release and recapturemechanism 200. When the implant 100 is radially expanded the implant 100can move axially toward the distal end of the implant 100, therebyexposing the implant actuation shaft 334 and tether line 210. Theoff-axis tension in the tether line 210 can create moment arms andbending bias which can cause the implant 100 to “jump,” move, rotate,etc., within the LAA 10 when the implant 100 is detached from theimplant delivery system, as is illustrated in FIG. 4C.

FIGS. 5A-C illustrate the implant release sequence of the implant 100with the implant release and recapture mechanism 200 of FIG. 3B. FIG. 5Aillustrates an example of an implant 100, an implant release andrecapture mechanism 200, a catheter system 300 where the implant releaseand recapture mechanism 200 is relatively stiff and extends over arelease mechanism length 202. Length 202 is shorter than length 201 ofFIG. 4A. FIG. 5B illustrates the expansion of the implant 100 withshorter moment arms and less bending bias than the systems illustratedin FIGS. 4A-C. As illustrated in FIG. 5C, the release of the implant 100from the catheter system 300 results in smaller moment arms and lessbending bias than in FIGS. 4A-C. The detachment of the implant 100results in less of a “jump” and reduced movement and/or rotation withinthe LAA 10.

1. Implant

FIG. 6 illustrates an implant 100 placed inside a LAA 10 of a heart 5,an implant release and recapture mechanism 200, and a catheter system300. In one embodiment, the implant 100 is a transluminally delivereddevice designed to occlude or contain particles within the LAA 10 andprevent thrombus from forming in, and emboli from originating from, theLAA 10. The delivery system 50 may be used to deliver the implant 100 toocclude or block the LAA 10 in a patient with atrial fibrillation. Thedelivery system 50 may be compatible for use with a transseptal sheath(not shown). The delivery system 50 and implant 100 may be selected toallow the implant 100 to be positioned, repositioned, and retrieved fromthe LAA 10 if necessary.

The implant 100 often includes a frame 101 and a membrane (not shown) ona proximal face 104 of the implant, such as described below. In anembodiment, the frame 101 is constructed of self-expanding nitinolsupports. The membrane may be constructed of a fabric covering, such asone made of ePTFE, or an ePTFE/PE laminate. To attach the membrane tothe frame 101, a PE mesh preferably is placed against the supports, withone sheet of ePTFE preferably placed over the PE mesh and another sheetof ePTFE preferably placed on an opposite side of the supports. Themembrane may be heated on both sides causing the PE to melt into bothsheets of ePTFE, thereby surrounding a portion of the frame 101. Thenitinol supports allow the implant 100 to self-expand in the appendage10, covering the orifice with the laminated fabric. The porous ePTFE/PElamination facilitates rapid endothelialization and healing.

In one embodiment, the implant 100 is expandable and collapsible. Theimplant 100 can include anchors that extend from the implant's frame 101when the implant 100 is expanded, as described below. The implant 100 isavailable in a range of sizes to accommodate the anatomy of a patient'sLAA 10. When used in the LAA 10, the implant 100 may have an expandeddiameter within the range of from about 1 cm to about 5 cm, and, in oneembodiment, about 3 cm. The overall axial length of the implant 10 fromits distal end 102 to its proximal end 104 is within the range of fromabout 1.5 cm to about 4 cm and, in one embodiment, about 2.5 cm.

In one embodiment, the delivery system 50 includes a transseptal, sheath520. A radiopaque marker 521 is located near the distal end of thetransseptal sheath 520.

FIGS. 7, 7A and 7B illustrate an implant 100 in accordance with anotherembodiment of the present invention. The implant 100 includes a distalend 102, a proximal end 104; and a longitudinal axis extendingtherebetween. A plurality of supports 106 extend between a distal hub108 and a proximal hub 110. At least two or three supports 106 areprovided, and in other embodiments, at least about ten supports 106 areprovided. In one embodiment, sixteen supports 106 are provided. However,the precise number of supports 106 can be modified, depending upon thedesired physical properties of the implant 100 as will be apparent tothose of skill in the art in view of the disclosure herein, withoutdeparting from the present invention.

In an embodiment, each support 106 includes a distal spoke portion 112,a proximal spoke portion 114, and an apex 116. Each of the distal spokeportion 112, the proximal spoke portion 114, and the apex 116 may be aregion on an integral support 106, such as a continuous rib or framemember which extends in a generally curved configuration as illustratedwith a concavity facing towards the longitudinal axis of the implant100. Thus, no distinct point or hinge at apex 116 is necessarilyprovided.

At least some of the supports 106, and, preferably, each support 106, isprovided with one or two or more anchors 118 or barbs 118. In theillustrated configuration, the implant 100 is in its enlargedorientation, such as for occluding a left atrial appendage 10 or otherbody cavity or lumen. In, this orientation, each of the barbs 118projects generally radially outwardly from the longitudinal axis, and isinclined in the proximal direction. One or more barbs may also beinclined distally, as is discussed elsewhere herein. In an embodimentwhere the barbs 118 and corresponding support 106 are cut from a singleribbon, sheet or tube stock, the barb 118 will incline radiallyoutwardly at approximately a tangent to the curve formed by the support106.

The illustrated anchor 118 is in the form of a barb, with at least oneon each support 106 for extending into tissue at or near the opening ofthe LAA 10. Depending upon the embodiment, two or three barbs 118 mayalternatively be desired on each support 106. In the single barb 118embodiment of FIG. 7, each barb 118 is inclined in a proximal direction.This is to inhibit proximal migration of the implant out of the leftatrial appendage 10. In this context, distal refers to the directioninto the left atrial appendage 10, and proximal refers to the directionfrom the left atrial appendage 10 into the heart 5.

Alternatively, one or more barbs 118 may face distally, to inhibitdistal migration of the implant 100 deeper into the LAA 10. Thus, theimplant 100 may be provided with at least one proximally facing barb 118and at least one distally facing barb 118. For example, in an embodimentof the type illustrated in FIG. 10, discussed below, a proximalplurality of barbs 118 may be inclined in a first direction, and adistal plurality of barbs 118 may be inclined in a second direction, toanchor the implant 100 against both proximal and distal migration.

The implant 100 constructed from the frame illustrated in FIG. 7 may beconstructed in any of a variety of ways, as will become apparent tothose of skill in the art in view of the disclosure herein. In onemethod, the implant 100 is constructed by laser cutting a piece of tubestock to provide a plurality of axially extending slots in-betweenadjacent supports 106. Similarly, each barb 118 can be laser cut fromthe corresponding support 106 or space in-between adjacent supports 106.The generally axially extending slots which separate adjacent supports106 end a sufficient distance from each of the proximal end 104 anddistal end 102 to leave a proximal hub 110 and a distal hub 108 to whicheach of the supports 106 will attach. In this manner, an integral cagestructure may be formed. Alternatively, each of the components of thecage structure may be separately formed and attached together such asthrough soldering, brazing, heat bonding, adhesives, and other fasteningtechniques which are known in the art.

A further method of manufacturing the implant 100 is to laser cut a slotpattern on a flat sheet of appropriate material, such as a flexiblemetal or polymer. The supports 106 may comprise a metal such asstainless steel, nitinol, Elgiloy, or others which can be determinedthrough routine experimentation by those of skill in the art. Wireshaving a circular or rectangular cross-section may be utilized dependingupon the manufacturing technique. In one embodiment, rectangular crosssection spokes are cut such as by known laser cutting techniques fromtube stock, a portion of which forms a proximal hub 110 or a distal hub108. The flat sheet may thereafter be rolled about an axis and opposingedges bonded together to form a tubular structure.

The apex portion 116 which carries the barb 118 may be advanced from alow profile orientation in which each of the supports 106 extendgenerally parallel to the longitudinal axis, to an implanted orientationas illustrated, in which the apex 116 and the barb 118 are positionedradially outwardly from the longitudinal axis. The support 106 may bebiased towards the enlarged orientation, or may be advanced to theenlarged orientation under positive force following positioning withinthe tubular anatomical structure, in any of a variety of manners.

Referring to FIGS. 8 and 9, the implant 100 may be provided with abather 120 such as a mesh or fabric. The barrier 120 may comprise any ofa variety of materials which facilitate cellular in-growth, such asePTFE. The suitability of alternate materials for barrier 120 can bedetermined through routine experimentation by those of skill in the art.The barrier 120 may be provided on either one or both axially facingsides of the implant 100. In one embodiment, the barrier 120 comprisestwo layers, with one layer on each side of a cage formed by a pluralityof supports 106. The two layers may be bonded to each other around thesupports 106 in any of a variety of ways, such as by heat bonding withor without an intermediate bonding layer such as polyethylene or FEP,adhesives, sutures, and other techniques which will be apparent to thoseof skill in the art in view of the disclosure herein. In an embodiment,the barrier 120 has a thickness of no more than about 0.003″ and aporosity within the range of from about 5 .mu.m to about 60 .mu.m.

Barrier 120 may be provided on only one hemisphere, proximal face 122,or may be carried by the entire implant 100 from proximal end 104 todistal end 102. The barrier may be secured to the radially inwardlyfacing surface of the supports 106, as illustrated in FIG. 9, or may beprovided on the radially outwardly facing surfaces of supports 106, orboth.

A further embodiment of the implant 100 is illustrated in FIG. 10, inwhich the apex 116 is elongated in an axial direction to provideadditional contact area between the implant 100 and the wall of thetubular structure. In this embodiment, one or two or three or moreanchors 118 may be provided on each support 106, depending upon thedesired clinical performance. The implant 100 illustrated in FIG. 10 mayalso be provided with any of a variety of other features discussedherein, such as a partial or complete barrier 120. In addition, theimplant 100 illustrated in FIG. 10 may be enlarged using any of thetechniques disclosed elsewhere herein.

FIG. 11 illustrates another embodiment of the present invention. Theimplant 100 may be in the form of any of those described previouslyherein, as modified below. In general, the implant 100 is movable from areduced crossing profile to an enlarged crossing profile. The implant100 is generally introduced into the body in its reduced crossingprofile, and when positioned at the desired deployment location, theimplant 100 is expanded to its enlarged crossing profile. When expanded,the implant 100 obstructs or filters the flow of desired particles,emboli, blood, etc., or performs other functions while positionedtherein.

The implant 100 may be biased in the direction of the enlarged crossingprofile, may be neutrally biased, or may be biased in the direction ofthe reduced crossing profile. Any modifications to the device anddeployment system to accommodate these various aspects of the implant100 may be readily accomplished by those of skill in the art in view ofthe disclosure herein.

The implant 100 is a detachable component of an adjustable implantdelivery system 50. The implant deliver system 50 generally includes acatheter 302 for inserting in implant into a patient's vasculature,advancing it percutaneously through the vasculature, positioning it at adesire deployment location, and deploying the implant 100 at thedeployment location, such as within a body cavity or lumen, as discussedabove. The catheter 302 generally includes an elongate flexible tubularbody 306 that extends between a proximal end 308 and a distal end 310.The catheter body has a sufficient length and diameter to permitpercutaneous entry into the vascular system and transluminal advancementthrough the vascular system to the desired deployment site.

For example, in an embodiment intended for access at the femoral veinand deployment within the left atrial appendage 50, the catheter 302 hasa length within the range of from about 50 cm to about 150 cm, and adiameter of generally no more than about 15 French. Further dimensionsand physical characteristics of catheters for navigation to particularsites within the body are well understood in the art and will not befurther described herein.

The tubular body 306 is further provided with a handle 402 generally onthe proximal end 308 of the catheter 302. The handle 402 permitsmanipulation of the various aspects of the implant delivery system 50,as will be discussed below. Handle 402 may be manufactured in any of avariety of ways, typically by injection molding or otherwise forming ahandpiece for single-hand operation, using materials and constructiontechniques well known in the medical device arts.

In the illustrated embodiment, the distal end 102 of the implant 100 isprovided with an implant plug 124. The implant plug 124 may be integralwith the distal end 102 of the implant or it may be a separate,attachable piece. Implant plug 124 provides a stopping surface 126 forcontacting an axially movable core 304 or other such similar structureas described herein. The core 304 extends axially throughout the lengthof the catheter body 302, and is attached at its proximal end to a corecontrol 404 on the handle 402. In some embodiments, the axially movablecore is referred to as a drive shaft or an implant actuation shaft. Inone embodiment, the implant plug 124 comprises an atraumatic tip, suchthat contact between the atraumatic tip and the inside surface of theLAA 10 does not cause significant damage to the LAA 10.

The core 304 may comprise any of a variety of structures which hassufficient lateral flexibility to permit navigation of the vascularsystem, and sufficient axial column strength to enable reduction of theimplant 100 to its reduced crossing profile. Any of a variety ofstructures such as hypotube, solid core wire, “bottomed out” coil springstructures, or combinations thereof may be used, depending upon thedesired performance of the finished device. In one embodiment, the core304 comprises stainless steel tubing.

The distal end of core 304 is positioned within a recess, cavity orlumen 132 defined by a proximally extending distal guide tube 130. Inthe illustrated embodiment, the distal guide tube 130 is a section oftubing such as metal hypotube, which is attached at the distal end 102of the implant and extends proximally within the implant 100. In someembodiments the distal guide tube 130 includes a distal end 102 of theimplant, an implant plug 124, and/or a stopping surface 126 as describedherein. The distal guide tube 130 preferably extends a sufficientdistance in the proximal direction to inhibit buckling or prolapse ofthe core 304 when distal pressure is applied to the core control 404 toreduce the profile of the implant 100. However, the guide tube 130should not extend proximally a sufficient distance to interfere with theopening of the implant 100.

As will be appreciated by reference to FIG. 11, the guide tube 130 mayoperate as a limit on distal axial advancement of the proximal end 104of implant 100. Thus, the guide tube 130 preferably does not extendsufficiently far proximally from the distal end 102 to interfere withoptimal opening of the implant 100. The specific dimensions aretherefore relative, and will be optimized to suit a particular intendedapplication. In one embodiment, the implant 100 has an implanted outsidediameter within the range of from about 5 mm to about 45 mm, and anaxial implanted length within the range of from about 5 mm to about 45mm. The guide tube 130 has an overall length of about 3 mm to about 35mm, and an outside diameter of about 0.095 inches. Additional disclosurerelating to this embodiment is discussed below, relating to FIGS. 11Aand 11B.

An alternate embodiment of a guide tube 130 is schematically illustratedin FIGS. 12A and 12B. In this configuration, the guide tube 130comprises a plurality of tubular segments 134 spaced apart by at leastone intervening space 136. This allows increased flexibility of theguide tube 130, which may be desirable during the implantation step,while retaining the ability of the guide tube 130 to maintain linearityof the core 304 while under axial pressure. Although three segments 134are illustrated in FIG. 12A and four segments are illustrated in FIG.12B, as many as 10 or 20 or more segments 134 may be desirable dependingupon the desired flexibility of the resulting implant. Each adjacentpair of segments 134 may be joined by a hinge element 138 which permitslateral flexibility. In the illustrated embodiment of FIG. 12A, thehinge element 138 comprises an axially extending strip or spine 138,which provides column strength along a first side of the guide tube 130.The guide tube 130 may therefore be curved by compressing a second sideof the guide tube 130 which is generally offset from the spine 138 byabout 180.degree. A limit on the amount of curvature may be set byadjusting the axial length of the space 136 between adjacent segments134. As illustrated in FIG. 12B, an embodiment of a guide tube 130 mayhave each axial spine 138 be rotationally offset from the next adjacentaxial spine 138 to enable flexibility of the overall guide tube 130throughout a 360.degree. angular range of motion.

Alternatively, the flexible hinge point 138 between each adjacentsegment 134 may be provided by cutting a spiral groove or plurality ofparallel grooves in a tubular element in between what will then becomeeach adjacent pair of segments 134. In this manner, each tubular element134 will be separated by an integral spring like structure, which canpermit flexibility. As a further alternative, the entire length of theguide tube 130 may comprise a spring. Each of the forgoing embodimentsmay be readily constructed by laser cutting or other cutting from apiece of tube stock, to produce a one piece guide tube 130.Alternatively, the guide tube 130 may be assembled from separatecomponents and fabricated together using any of a variety of bondingtechniques which are appropriate for the construction material selectedfor the tube 320.

Various distal end 102 constructions may be utilized, as will beapparent to those of skill in the art in view of the disclosure herein.In the illustrated embodiment, the distal implant plug 124 extendswithin the implant 100 and is attached to the distal end of the guidetube 130. The implant plug 124 may be secured to the guide tube 130 andimplant 100 in any of a variety of ways, depending upon the variousconstruction materials. For example, any of a variety of metal bondingtechniques such as a welding, brazing, interference fit such as threadedfit or snap fit, may be utilized. Alternatively, any of a variety ofbonding techniques for dissimilar materials may be utilized, such asadhesives, and various molding techniques. In one construction, theimplant plug 124 comprises a molded polyethylene cap, and is held inplace utilizing a distal cross pin 140 which extends through the implant100, the guide tube 130 and the implant plug 124 to provide a secure fitagainst axial displacement.

Some left atrial appendage implants, such as some of those described insome of the embodiments above (for examples, see FIGS. 11-12B) and below(e.g., see FIG. 14-16B), include a single guide tube 130 at the distalend 102 of the implant 100 that connects to or engages an implantactuation shaft and provides axial load transmission from the distalguide tube 130 to the implant 100 at its distal end 102. In someembodiments, the shaft may be an implant actuation shaft 334, an axiallymoveable core 304 or rotatable core 342.

When the implant actuation shaft is particularly flexible or relativelylong for actuation of a long implant 100, it could buckle if notadequately supported within the implant 100. To prevent bending orbuckling of the implant actuation shaft 334, support preferably isprovided only inside the implant 100 in order to maintain the interfacewith a catheter system 300 proximal and adjacent to the implant 100 asflexible as possible. Given the continuously changing length of theimplant 100 depending on its expansion state, a support member that alsochanged length with the implant 100 would be useful as well.

FIGS. 13A and 13B illustrate an alternate embodiment of an implant 100,which includes multiple guide tubes 162, 164. The implant 100 includestwo substantially concentric or axially aligned telescoping guide tubes162, 164, which are slidably moveable with respect to one another. Theouter guide tube 162 is attached to the implant's distal end 102 or maybe integrally formed therewith, and the inner guide tube 164 is attachedto its proximal end 104 or may be integrally formed therewith, althoughin other embodiments they are attached to proximal and distal ends,respectively. In a concentric embodiment, the outer guide tube 162 hasan internal diameter sufficiently large enough to contain the outerdiameter of the inner guide tube 164. In certain embodiments, thetelescoping guide tubes 162 and 164 perform a support function when eachis anchored at either the distal end 102 or proximal end 104 of theimplant 100 and by freely floating at the interface between telescopingguide tubes 162 and 164.

The outer guide tube 162 and the inner guide tube 164 are sized to allowfull support of an implant actuation shaft 334 without increasing thecollapse force used to reduce the implant's diameter. The telescopingguide tubes 162 and 164 can be utilized with embodiments having adisconnect mount 236 (see FIGS. 17-21), tethered embodiments, or anyother embodiments disclosed herein.

Referring to FIG. 13A, when the implant 100 is in a radially reducedstate, the inner guide tube 164 overlaps the outer guide tube 162, asshown. Alternatively, the inner guide tube 164 may not overlap with theouter guide tube 162 in the radially reduced state of the implant 100.Referring to FIG. 13B, when the implant 100 is radially expanded, theinner guide tube 164 slides into the outer guide tube 162 as the overalllength of the implant 100 is axially shortened. The outer guide tube 162can have a flared end to facilitate collapse of the implant 100. Aflared end of the outer guide tube 162 can help guide the inner guidetube 164 during expansion. Similarly, the inner guide tube 164 can havea tapered end.

In some embodiments of an implant 100 with multiple guide tubes, eitherof the outer guide tube 162 or the inner guide tube 164 may also be adistal guide tube 130 or a proximal guide tube 160. The outer guide tube162 can be a distal guide tube 130 attached at its distal end to thedistal end 102 of the implant 100, and the inner guide tube 164 can be aproximal guide tube 160 attached at its proximal end to the proximal end104 of the implant 100. The outer guide tube 162 may include a matingsurface on or near its distal end to engage a mating surface on thedistal hub 108, or elsewhere on the implant 100.

Relative proximal and distal movement of the inner guide tube 164 andouter guide tube 162 is preferably limited by a motion limit. In oneembodiment, the motion limit includes at least one cross pin. In otherembodiments, the motion limit includes at least one flare, annular ring,bump, or other suitable mechanism as is well known to those of skill inthe art. The outer guide tube 162 slidably engages the inner guide tube164, which preferably enters the proximal end of the outer guide tube162. One advantage of this embodiment is a reduction in the likelihoodthat the insertion of an implant actuation shaft 334 into the implant100 will bind on the proximal end of distal guide tube 130 whileassembling a implant delivery system 50 or while attempting to recapturea detached implant 100. Alternatively, in another embodiment, the outerguide tube 162 can be attached at its proximal end to the proximal end104 of the implant 100, and the inner guide tube 164 can be attached atits distal end to the distal end 102 of the implant 100.

In an embodiment of an implant 100 with multiple guide tubes, the distalguide tube 130 has a distal guide tube lumen 132 and the proximal guidetube 160 has a proximal guide tube lumen 170. These lumens 132 and 170may contain radiopaque or contrast materials injected into the cathetersystem 300 through ports in the deployment handle 400. The proximalguide tube 160 may have a window 170 that passes through the wall of theproximal guide tube 160. The window 170 may be used to release contrastmaterials in the proximal guide tube lumen 170 toward the proximal end104 of the implant 100. This window 170 may also be used as an anchorpoint or port through which a pull wire 312 from a catheter system 300may be used to secure the implant 100 prior to detachment.

In certain embodiments of an implant 100 with multiple guide tubes, aslideable engagement surface 166 of the outer guide tube 162 mayinterface with a slideable engagement surface 168 of the inner guidetube 164. Various embodiments of the outer guide tube 162 and innerguide tube 164 may comprise generally circular cross sections whichallow free rotation about the concentric axis of the guide tubes alongthe generally coaxial cylindrical slideable engagement surfaces 166 and168. Alternatively, other embodiments may have slideable engagementsurfaces 166 and 168 which are elliptically-shaped or contain certainkey and slot configurations or similar interface configurations known inthe art to prevent or reduce relative rotation between the outer guidetube 162 and inner guide tube 164. Depending on how the guide tubes areattached to the ends of the implant 100, these rotation-inhibitingembodiments may provide additional support to reduce rotation in theframe 101 of the implant 100.

In some embodiments of the implant actuation shaft 334, the shaft may bean axially moveable core 304, a rotatable core 342, or a shaft that usesan unscrew-to-release mechanism similar to an embodiment as illustratedin FIG. 14 (see below). By using two telescoping guide tubes 130 and160, the free detensioned length of the implant 100 can be doubled.

Further advantages of multiple guide tube embodiments are described inthe context of an improved implant release and recapture mechanism.

2. Implant Release and Recapture Mechanisms

Various embodiments of implant release and recapture mechanisms providean interface between an implant and a catheter system used to deploy,detach, and recapture the implant.

a. Pull Wire Mechanisms

Referring back to FIG. 11, there is illustrated an embodiment of animplant delivery system 50 with a detachable implant 100, an implantrelease and recapture mechanism 200, a catheter system 300, and adeployment handle 400. As illustrated in this embodiment, the implantrelease and recapture mechanism 200 includes a release element, such asa pull wire 312, which keeps the proximal end 104 of the implant 100 intension. An axially moveable core 304 simultaneously pushes against thedistal end 102 of the implant 100. The combination of pulling on theimplant proximal end 104 while pushing on its distal end 102 keeps theimplant 100 in a compressed state. When either the core 304 is pulledproximally or the pull wire 312 is allowed to move distally, the tensionon the ends of the implant 100 is reduced, thereby allowing the springloaded or shape memory material in the implant 100 to radially expandinto its normal expanded state.

In this embodiment, the proximal end 104 of the implant 100 is providedwith a releasable lock 142 for attachment to a pull wire 312. Pull wire312 extends proximally throughout the length of the tubular body 306 toa proximal pull wire control 406 on the handle 402.

As used herein, the term pull wire is intended to include any of a widevariety of structures which are capable of transmitting axial tension orcompression such as a pushing or pulling force with or without rotationfrom the proximal end 308 to the distal end 310 of the catheter 302.Thus, monofilament or multifilament metal or polymeric rods or wires,woven or braided structures may be utilized. Alternatively, tubularelements such as a concentric tube positioned within the outer tubularbody 306 may also be used as will be apparent to those of skill in theart.

In the illustrated embodiment in FIG. 11, the pull wire 312 isreleasably connected to the proximal end 104 of the implant 100. Thispermits proximal advancement of the proximal end of the implant 100,which cooperates with a distal retention force provided by the core 304against the distal end of the implant to axially elongate the implant100 thereby reducing it from its implanted configuration to its reducedprofile for implantation. The proximal end of the pull wire 312 may beconnected to any of a variety of pull wire controls 406, includingrotational knobs, levers and slider switches, depending upon the designpreference.

The implant delivery system 50 thus permits the implant 100 to bemaintained in a low crossing profile configuration, to enabletransluminal navigation to a deployment site. Following positioning ator about the desired deployment site, proximal retraction of the core304 enables the implant 100 to radially enlarge under its own bias tofit the surrounding tissue structure. Alternatively, the implant can beenlarged under positive force, such as by inflation of a balloon or by amechanical mechanism. Once the clinician is satisfied with the positionof the implant 100, such as by injection of dye and visualization usingconventional techniques, the core 304 is proximally retracted therebyreleasing the lock 142 and enabling detachment of the implant 100 fromthe deployment system 300.

If, however, visualization reveals that the implant 100 is not at thelocation desired by the clinician, proximal retraction of the pull wire312 with respect to the core 304 will radially reduce the diameter ofthe implant 100, thereby enabling repositioning of the implant 100 atthe desired site. Thus, the present invention permits the implant 100 tobe enlarged or reduced by the clinician to permit repositioning and/orremoval of the implant 100 as may be desired.

The proximal end 104 of the implant 100 is preferably provided with areleasable lock 142 for attachment of the pull wire 312 to thedeployment catheter 302. In the illustrated embodiment in FIG. 11, thereleasable lock 142 is formed by advancing the pull wire 312 distallyaround a proximal cross pin 146, and providing an eye or loop whichextends around the core 304. As long as the core 304 is in positionwithin the implant 100, proximal retraction of the pull wire 312 willadvance the proximal end 104 of the implant 100 in a proximal direction.See FIG. 11A. However, following deployment, proximal retraction of thecore 304 such as by manipulation of the core control 404 will pull thedistal end of the core 304 through the loop on the distal end of thepull wire 312. The pull wire 312 may then be freely proximally removedfrom the implant 100, thereby enabling detachment of the implant 100from the delivery system 50 within a treatment site. See FIG. 11B.

The embodiment illustrated in FIGS. 11, 11A and 11B may impart bias tothe implant 100 because the location of the cross pin 146 creates amoment arm with respect to the core 304 when tension is applied to thepull wire 312 in order to maintain the implant 100 in a radially-reducedconfiguration. Tension through the pull wire 312 may be on the order ofsix pounds of force, which when loaded off-center by the pull wire 312over the distance between the center of the core 304 over the cross pin146 may result in significant torque and bias on the implant 100 whileit is being deployed in the LAA 10. This bias may result in deflectionin the delivery system 50 which may cause the implant 100 to jump, move,rotate, etc., when released from the catheter system 300 duringdetachment.

b. Threadable Torque Rod Mechanisms

FIG. 14 illustrates an alternate embodiment of an implant deploymentsystem 50 in which an implant 100 is radially enlarged or reduced byrotating a torque element extending throughout the deployment catheter.This embodiment of the implant deployment system 50 reduces the bias ofmoment arms described in the previous embodiment by eliminatingoff-center pull wires 312 (as illustrated in FIGS. 11, 11A and B).Instead, the elongate flexible tubular body 306 of the deploymentcatheter 302 includes a rotatable torque rod 340 extending axiallytherethrough. The proximal end of the torque rod 340 may be connected ata proximal manifold to a manual rotation device such as a hand crank,thumb wheel, rotatable knob or the like. Alternatively, the torque rod340 may be connected to a power driven source of rotational energy suchas a motor drive or air turbine. The distal end of the torque rod 340 isintegral with or is connected to a rotatable core 342 which extendsaxially through the implant 100. A distal end 344 of the rotatable core342 is positioned within a cavity 132 as has been discussed.

The terms torque rod or torque element are intended to include any of awide variety of structures which are capable of transmitting arotational torque throughout the length of a catheter body. For example,solid core elements such as stainless steel, nitinol or other nickeltitanium alloys, or polymeric materials may be utilized. In anembodiment intended for implantation over a guidewire, the torque rod340 is preferably provided with an axially extending central guidewirelumen. This may be accomplished by constructing the torque rod 340 froma section of hypodermic needle tubing, having an inside diameter of fromabout 0.001 inches to about 0.005 inches or more greater than theoutside diameter of the intended guidewire. Tubular torque rods 340 mayalso be fabricated or constructed utilizing any of a wide variety ofpolymeric constructions which include woven or braided reinforcinglayers in the wall. Torque transmitting tubes and their methods ofconstruction are well understood in the intracranial access androtational atherectomy catheter arts, among others, and are notdescribed in greater detail herein.

Use of a tubular torque rod 340 also provides a convenient infusionlumen for injection of contrast media within the implant 100, such asthrough a port 343 or lumen 350. In one embodiment, axially moveablecore 304 also includes a lumen 350. The lumen 350 preferably allowsvisualization dye to flow through the lumen 350 of the axially moveablecore 304, through the lumen 150 of the implant end cap 148, and into theleft atrial appendage 10. Such usage of visualization dye is useful forclinical diagnosis and testing of the position of the implant 100 withinthe left atrial appendage 10 or other body opening, as described ingreater detail below.

The marker 360 as shown in FIG. 14 advantageously assists in locatingthe position of the distal end 344 of the axially moveable core 342. Inone embodiment, marker 360 comprises a radiopaque band press fit ontothe distal end 344 of the axially moveable core 342. Marker 360preferably is made from a material readily identified after insertioninto a patient's body by using visualization techniques that are wellknown to those of skill in the art. In one embodiment, the marker 360 ismade from gold, or tungsten, or any such suitable material, as is wellknown to those of skill in the art. In another embodiment, marker 360 iswelded, soldered, or glued onto the distal end 344 of the axiallymoveable core 342. In one embodiment, marker 360 is an annular band andsurrounds the circumference of the axially moveable core 342. In otherembodiments, the marker 360 does not surround the circumference of theaxially moveable core 342. In other embodiments, marker 360 includesevenly or unevenly spaced marker segments. In one embodiment, the use ofmarker segments is useful to discern the radial orientation of theimplant 100 within the body.

The proximal end 104 of the implant 100 is provided with a threadedaperture 346 through which the core 342 is threadably engaged. As willbe appreciated by those of skill in the art in view of the disclosureherein, rotation of the threaded core 342 in a first direction relativeto the proximal end 104 of the implant 100 will cause the rotatable core342 to advance distally. This distal advancement will result in an axialelongation and radial reduction of the implantable device 100. Rotationof the rotatable core 342 in a reverse direction will cause a proximalretraction of the rotatable core 342, thus enabling a radial enlargementand axial shortening of the implantable device 100.

The deployment catheter 302 is further provided with an anti-rotationlock 348 between a distal end 310 of the tubular body 306 and theproximal end 104 of the implant 100. In general, the rotational lock 348may be conveniently provided by cooperation between a first surface 352on the distal end 310 of the deployment catheter 302, which engages asecond surface 354 on the proximal end 104 of the implant 100, torotationally link the deployment catheter 302 and the implantable device100. Any of a variety of complementary surface structures may beprovided, such as an axial extension on one of the first 352 and secondsurfaces 354 for coupling with a corresponding recess on the other ofthe first 352 and second surfaces 354. Such extensions and recesses maybe positioned laterally offset from the axis of the catheter 302.Alternatively, they may be provided on the longitudinal axis with any ofa variety of axially releasable anti-rotational couplings having atleast one flat such as a hexagonal or other multifaceted cross-sectionalconfiguration.

Upon placement of the implant 100 at the desired implantation site, thetorque rod 340 is rotated in a direction that produces an axial proximalretraction. This allows radial enlargement of the radially outwardlybiased implant 100 at the implantation site. Continued rotation of thetorque rod 340 will cause the threaded core 342 to exit proximallythrough the threaded aperture 346. At that point, the deploymentcatheter 302 may be proximally retracted from the patient, leaving theimplanted device 100 in place.

By modification of the decoupling mechanism to allow the core 342 to bedecoupled from the torque rod 340, the rotatable core 342 may be leftwithin the implant 100, as may be desired depending upon the intendeddeployment mechanism. For example, the distal end of the core 342 may berotatably locked within the end cap 148, such as by includingcomplimentary radially outwardly or inwardly extending flanges andgrooves on the distal end of the core 342 and inside surface of thecavity 132. In this manner, proximal retraction of the core 342 byrotation thereof relative to the implant 100 will pull the end cap 148in a proximal direction under positive force. This may be desirable as asupplement to or instead of a radially enlarging bias built into theimplant 100.

In other embodiments, the torque rod 340 is threaded at its distal end.The distal end is threaded into a sliding nut located within a guidetube extending from the distal end of the implant 100. Such embodimentsare described in greater detail in U.S. application Ser. No. 10/642,384,filed Aug. 15, 2003, published as U.S. Publication No. 2005/0038470,which is expressly incorporated by reference herein. Another embodimentof an implant deployment system that could include a torque rod threadedat its distal end in a manner similar to an embodiment illustrated inFIG. 16A.

The implant 100 may also be retrieved and removed from the body inaccordance with a further aspect of the present invention. One manner ofretrieval and removal is described with respect to FIGS. 15A-E.Referring to FIG. 15A, an implanted device 100 is illustrated asreleasably coupled to the distal end of the tubular body 306, as hasbeen previously discussed. Coupling may be accomplished by aligning thetubular body 306 with the proximal end 104 of the deployed implant 100,under fluoroscopic visualization, and distally advancing a rotatablecore 342 through the threaded aperture 346. Threadable engagementbetween the rotatable core 342 and aperture 346 may thereafter beachieved, and distal advancement of core 342 will axially elongate andradially reduce the implant 100.

The tubular body 306 is axially movably positioned within an outertubular delivery or retrieval catheter 502. In various embodiments, theretrieval catheter 502 may be separate and distinct from the delivery ordeployment catheter 302, or the retrieval catheter 502 may be coaxialwith the delivery or deployment catheter 302, or the retrieval catheter502 may be the same catheter as the delivery or deployment catheter 302.Catheter 502 extends from a proximal end (not illustrated) to a distalend 506. The distal end 506 is preferably provided with a flaredopening, such as by constructing a plurality of petals 510 forfacilitating proximal refraction of the implant 100 as will becomeapparent.

Petals 510 may be constructed in a variety of ways, such as by providingaxially extending slits in the distal end 506 of the catheter 502. Inthis manner, preferably at least about three, and generally at leastabout four or five or six petals or more will be provided on the distalend 506 of the catheter 502. Petals 510 manufactured in this mannerwould reside in a first plane, transverse to the longitudinal axis ofthe catheter 502, if each of such petals 510 were inclined at 90 degreesto the longitudinal axis of the catheter 502.

In one embodiment, a second layer of petals 512 are provided, whichwould lie in a second, adjacent plane if the petals 512 were inclined at90 degrees to the longitudinal axis of the catheter 502. Preferably, thesecond plane of petals 512 is rotationally offset from the first planeof petals 510, such that the second petals 512 cover the spaces 514formed between each adjacent pair of petals 510. The use of two or morelayers of staggered petals 510 and 512 has been found to be useful inretrieving implants 100, particularly when the implant 100 carries aplurality of tissue anchors 118. However, in many embodiments, theretrieval catheter 502 includes only a single plane of petals 510, suchas illustrated in FIG. 15B.

The petals 510 and 512 may be manufactured from any of a variety ofpolymer materials useful in constructing medical device components suchas the catheter 502. This includes, for example, polyethylene, PET,PEEK, PEBAX, and others well known in the art. The second petals 512 maybe constructed in any of a variety of ways. In one convenientconstruction, a section of tubing which concentrically fits over thecatheter 502 is provided with a plurality of axially extending slots inthe same manner as discussed above. The tubing with a slotted distal endmay be concentrically positioned on the catheter 502, and rotated suchthat the space between adjacent petals 512 is offset from the spacebetween adjacent petals 510. The hub of the petals 512 may thereafter bebonded to the catheter 502, such as by heat shrinking, adhesives, orother bonding techniques known in the art. FIG. 15B shows a perspectiveview of an embodiment of a single layer of petals 510 which is coaxialwith a transseptal catheter 520 and an implant actuation shaft 334. Theimplant actuation shaft 334 can be rotatable core 342 as illustrated inFIG. 15A.

The removal sequence will be further understood by reference to FIGS.15C through 15E. Referring to FIG. 15C, the radially reduced implant 100is proximally retracted part way into the retrieval catheter 502. Thiscan be accomplished by proximally retracting the tubular body 306 and/ordistally advancing the catheter 502. As illustrated in FIG. 15D, thetubular body 306 having the implant 100 attached thereto is proximallyretracted a sufficient distance to position the tissue anchors 118within the petals 510. The entire assembly of the tubular body 306,within the retrieval catheter 502 may then be proximally retractedwithin the transseptal sheath 520 or other tubular body as illustratedin FIG. 15E. The collapsed petals 510 allow this to occur whilepreventing engagement of the tissue anchors 118 with the distal end ofthe transseptal sheath 520 or body tissue. The entire assembly havingthe implant 100 contained therein may thereafter be proximally withdrawnfrom or repositioned within the patient.

The embodiments illustrated in FIGS. 14 and 15 may impart bias to theimplant 100 because relative rotation between the catheter system 300and the implant 100 is required in order to release the threaded lockingsystem described above. When the implant 100 is to be radially expandedwithin the LAA 10 the torque rod 342 must be rotated with respect to thethreaded aperture 346 in the implant 100. The rotation of the rod withrespect to the implant may result in torque, causing a rotational biasin the implant 100 with respect to the LAA 10 as well as with respect tothe catheter system 300. This bias may result in deflection in thedelivery system 50 which may cause the implant 100 to “jump” or “spin”when released from the catheter system 300 during detachment.

c. Axial Decoupling Mechanisms

FIGS. 16A and 16B illustrate another embodiment of an implant deliverysystem 50. The system 50 of the illustrated embodiment provides someaxial decoupling between an axially moveable core 304 and an implant100. This embodiment of the implant deployment system 50 reduces thebias of torsion loads described in the previous embodiment byeliminating rotational forces related to a threaded engagement betweenan implant 100 and a catheter system 300 (as illustrated in FIGS. 14 and15). Furthermore, it is clinically advantageous to provide axialdecoupling between the axially moveable core 304 and the implant 100 isbecause axial decoupling assures that movement of the axially moveablecore 304, as well as other components of the adjustable implant deliverysystem 50 that are coupled to the axially moveable core 304 (forexample, but not limited to the deployment handle 400 and the cathetersystem 300, described further herein), do not substantially affect theshape or position of the implant 100. Such axial decoupling preventsinadvertent movement of the axially moveable core 304 or deploymenthandle 400 from affecting the shape or position of implant 100.

For example, in one embodiment, if the user inadvertently pulls orpushes the axially moveable core 304 or the deployment handle 400, theposition of the implant 100 within the left atrial appendage 10preferably will not be substantially affected. In addition, axialdecoupling also preferably prevents the motion of a beating heart 5 fromtranslating into movement of the axially moveable core 304, the catheter300, and/or the components coupled to the axially moveable core 304 andcatheter 300, including the deployment handle 400. By decoupling theimplant 100 from the axially moveable core 304 and other componentscoupled to the axially moveable core 304, the risk of accidentallydislodging the implant 100 from the left atrial appendage 10 is reduced.

The illustrated implant release and recapture mechanism 200 of FIGS. 16Aand 16B provides quick-disconnect functionality for release of axiallymoveable core 304 from guide tube 130 by using non-rotational forces. Asillustrated, the implant release and recapture mechanism 200 includes aguide tube 130, which comprises at least one slot 154. Two opposingslots 154 are shown in the embodiment of FIGS. 16A and 16B. Axiallymoveable core 304 is coupled to guide tube 130 by quick-disconnectfunctionality.

Axially moveable core 304 in this embodiment includes a retractable lock220 in the form of an elongate key 222 extending through the lumen ofthe core 304, and two opposing ports 224 in axially moveable core 304through which two tabs 226 extend. The distal tip 228 of the key 222includes a contact surface 230 operable to engage contact surfaces 232of the tabs 226. The key 222 is moveable relative to the axiallymoveable core 304, and can be moved distally such that contact surface230 engages contact surfaces 232 of tabs 226, translating into radialmovement of tabs 226. Radial movement of tabs 226 causes them to projectinto slots 154 of the guide tube 130 by bending radially outwardly, andextending in a substantially radial direction. In one embodiment, thekey 222 is secured in place relative to the axially moveable core 304,so that the tabs 226 remain projected into the slots 154 of the guidetube 130. With the tabs 226 secured in place, axial movement of axiallymoveable core 304 preferably is limited by interference between the tabs226 and the proximal and distal surfaces 156, 158 of guide tube 130.

In one embodiment, the key 222 is made from an elongate wire, rod, ortube flexible enough for delivery through the adjustable implantdelivery system 50 described above, and strong enough to apply enoughforce to tabs 226 to achieve the functionality described above. In oneembodiment, the key 222 is made from stainless steel. The key 222preferably is locked in place relative to the axially moveable core 304by using a control, such as a thumbswitch or other such device as iswell known to those of skill in the art. For example, in one embodiment,the axially moveable core 304 is secured to the proximal portion of adeployment handle 400 (not shown) such that the position of the axiallymoveable core 304 is fixed with respect to the deployment handle 400. Akey 222 preferably is inserted inside of the axially moveable core 304such that it may slide axially within the axially moveable core 304. Theproximal portion of the key 222 preferably is coupled to a control, suchas, for example, a thumbswitch. The thumbswitch preferably is providedsuch that it may slide axially with respect to the deployment handle 400(and therefore with respect to the axially moveable core 304) over apredetermined range. By coupling the thumbswitch to the proximal portionof the key 222, axial movement of the key 222 with respect to theaxially moveable core 304 is achieved over the predetermined range. Inaddition, by locking the thumbswitch in place (by using mechanisms wellknown to those of skill in the art, such as release buttons, tabs, ortheir equivalents), the key 222 may be locked in place with respect tothe axially moveable core 304. Alternatively, switches, levers, buttons,dials, and similar devices well known to those of skill in the art maybe used instead of a thumbswitch as the control for the retractable lock220.

To decouple axially moveable core 304 from the guide tube 130,retractable lock 220 is released by moving key 222 proximally relativeto axially moveable core 304, thereby removing radial forces fromcontact surfaces 232 of tabs 226. In one embodiment, tabs 226 are biasedto bend inward upon the removal of the radial forces from their contactsurfaces 232. For example, tabs 226 preferably are constructed from aspring material, or a shape memory metal, such as, for example, nickeltitanium. Alternatively, in another embodiment, key 222 is moveddistally to decouple axially moveable core 304 from the guide tube 130.For example, in one embodiment, key 222 includes a cutout, notch, orslot along at least a portion of its distal end. In one embodiment, asthe key 222 is moved distally, the cutout, notch, or slot is moved suchthat it engages the tabs 226, allowing them to flex inwardly preferablyunder their own bias. In another embodiment, tabs 226 are biased to bendoutward upon removal of a radial force from a contact surface 232, andbend inward upon application of a radial force to contact surface 232.In such embodiment, the key 222 preferably is advanced distally to applyforce on a contact surface 232 such that tabs 226 are directed inward.In one embodiment, the key 222 is advanced proximally to apply force ona contact surface 232 such that tabs 226 are directed inward.

In other embodiments, a guide tube 130 need not be connected to theimplant 100, and for example, can be provided as part of the axiallymoveable core 304, or even the deployment handle 402 in order todecouple axial movement between the implant 100 and the rest of thedelivery system 50. For example, in one embodiment, an axially moveablecore may include two concentric or axially aligned tubes, slidablymoveable with respect to one another, such as, for example, an outertube and an inner tube, such as describe above with respect to FIGS. 13Aand 13B. The outer tube may include a mating surface on or near itsdistal end to engage a mating surface on the distal hub, or elsewhere onthe implant. The outer tube slidably engages an inner tube, which entersthe outer tube at the outer tube's proximal end. In one embodiment, asolid core is used instead of an inner tube. Relative proximal anddistal movement of the inner and outer tube is preferably limited by amotion limit.

In one embodiment, the motion limit includes at least one cross pin. Inother embodiments, the motion limit includes at least one flare, annularring, bump, or other suitable mechanism as is well known to those ofskill in the art. The inner tube extends preferably to a handle asdescribed above for operating the axially moveable core. The engagementof the outer tube and the inner tube of the axially moveable core mayoccur anywhere between the handle and the implant along the length ofthe core.

In another embodiment, the inner tube includes a mating surface on itsdistal end to engage a mating surface on the distal hub of the implant.The inner tube slidably engages an outer tube, which at least partiallycovers the inner tube at the inner tube's proximal end. Relativeproximal and distal movement of the inner and outer tube is preferablylimited by a motion limit as described above, with the outer tubeextending outside of the patient and operably connected to a handle.

d. Multiple Guide Tube Mechanisms

Again referring to FIGS. 13A and 13B, various embodiments of a multipleguide tube system may provide additional buckling and bending supportfor any implant actuation shaft 334 traversing an axis of an implant100, as described above. Also, providing dual, opposed guide tube allowsdecoupling of implant motion with respect to the delivery catheter overa longer axial distance. For example, a single guide tube having mayallow for axial movement decoupling over the length of the single guidetube, but dual guide tubes allow for axial movement decoupling over thelength defined by both guide tubes.

Single guide tube embodiments are illustrated in FIGS. 16A and 16B, anddescribed in U.S. application Ser. No. 10/642,384, filed Aug. 15, 2003,published as U.S. Publication No. 2005/0038470, incorporated byreference herein. Implants including single guide tubes generallyinclude a nut that is configured to slide within the guide tube along alimited axial range of motion. A tab, or protrusion, generally extendsfrom the external side wall of the nut into a slot provided in the guidetube wall. The interference between the tab and the slot defines anaxial range of motion provided by the guide tube/sliding nut assembly.An axial moveable core, or a torque rod, is generally coupled to the nut(e.g., a threaded portion of the core screws into a mating portion ofthe nut), and an implant is generally coupled to the distal end of thesingle guide tube; therefore, the axial range of motion defined by theguide tube/sliding nut assembly also defines an axial range of motionbetween the axial moveable core and the implant.

The axial range of motion between the axial moveable core and theimplant defines a distance over which axial movement of the implant isdecoupled from the axial moveable core. This decoupling distanceprovides many clinical advantages. For example, once the implant isexpanded within the patient's heart, such as within the LAA, itgenerally remains attached to the axial moveable core. By remainingattached to the axial moveable core the clinician can verify the implantposition and sealing against the LAA wall prior to final deployment, orrelease, from the axial moveable core.

Forces provided by the patient's moving heart act upon the core-coupledimplant. It is desirable that the implant is free to move with themovement of the patient's beating heart, and that the implant does notresist such forces. Resistance to heart movement could cause the implantto become dislodged from its implantation site, or to change itorientation in an undesired manner.

The guide tube/sliding nut assembly of the single guide tube embodimentsaddresses this issue by providing limited decoupling between the implantand an axial moveable core, as discussed above. However, the decouplinglength is generally limited by the length of the guide tube slot, whichis limited by the guide tube length. It would be advantageous toincrease the decoupling length. In one embodiment, decoupling length isincreased by employing a dual guide tube configuration, such asdescribed above with respect to FIGS. 13A and 13B, and below. Inaddition, a dual guide tube configuration can be employed with any ofthe deployment systems, delivery systems, implants, catheters, andcatheter systems described herein.

Although the embodiments of FIGS. 13A and 13B illustrate one pull cordor tether 312 configuration, certain preferred embodiments of an implantdelivery system 50 with a multiple guide tubes do not include a pullcord 312. Removing the tether 312 can reduce system bias from momentarms. Instead, an embodiment of an implant delivery system 50 with amultiple guide tubes 130 and 160, or 164 and 162, may be used with athreaded rod 342 configuration as described above relating to FIGS. 14and 15. In other embodiments, an implant delivery system 50 withmultiple guide tubes does not use a threaded torque rod configuration inorder to reduce system bias from rotation of the implant 100 withrespect to a torque rod 342.

In certain embodiments an implant delivery system 50 with multiple guidetubes can provide for some axial load decoupling by providing slideableaxial support to an implant 100, which is attached at its proximal end104 to a catheter system 300. After an implant actuation shaft 334 iswithdrawn from the distal end 102 of an implant, the freely slideableconcentric guide tubes 130 and 160 (or 162 and 164) may absorb some ofthe axial loading caused by the beating of a heart 5, thereby allowingthe implant 100 frame 101 to deform with the beating of a heart 5without imparting a complete load to the remainder of the implantdelivery system 50.

In one embodiment, a multiple guide tube configuration may be used tosimplify an implant release and recapture mechanism 200. For example,the implant release and recapture mechanism 200 provides extendablesupport to a non-threaded shaft 334 that provides axial force to thedistal end 104 of an implant 100 without providing off-center momentarms or rotational loads relative to the implant 100 during implantdeployment or detachment (such as is illustrated in one embodiment inFIGS. 21A-21C, as described below).

In one embodiment, multiple guide tubes provide additional axial supportand guided slidable surfaces to the implant 100 while preventing theshaft 334 from buckling over a the guide tube lengths. Substantiallycoaxial tubes provide for easier alignment of the ends 102 and 104 of animplant 100, and simplify the re-insertion of a shaft 334 into animplant 100 during recapture of detached or deployed implants. Inaddition, the multiple guide tube configuration provides support for thedistal loading provided by the shaft 334, and works with any collapse orrelease mechanism. However, it would be advantageous to provide thenecessary proximal loading to the proximal end 104 of an implant 100 inorder to radially reduce an implant 100 in a manner that did not impartmoment arms or rotational loads to the implant 100 during deployment ordetachment, as described in the following embodiments.

e. Concentric Collapse and Release Mechanisms

FIGS. 17-21 illustrate cross-sectional views of various embodiments ofthe distal end of an implant delivery system 50 that includes an implant100, an implant release and recapture mechanism 200, and a cathetersystem 300, which is attachable to a deployment handle 400 (notillustrated). The illustrated embodiments provide mechanisms to releasean implant 100 from a catheter system 300 such that the implant'sposition and orientation do not change as a result of the releaseprocess. For example, the illustrated embodiments reduce bias and momentarms that cause deformation of the implant 100 and loads within theimplant delivery system 50. Such bias and moment arms can cause theimplant 100 to jump or change orientation when released from the implantdelivery system 50. These embodiments include a flexible interfacebetween the implant 100 and the catheter system 300. They also reduceoff-axis loading, thereby reducing moment arms and bending bias withinthe system 50. Some embodiments include a tether line 210 system (notshown) or a torque rod 340 configuration (not shown), as describedabove.

Referring to FIGS. 17-20, the illustrated embodiments have an implant100 with a frame 101, a proximal end 104 and a distal end 102, astopping surface 126 at the distal end 102 of the implant 100, and adisconnect mount interface 180 on the proximal end 104 of the implant100. The implant of FIGS. 17-20 is schematically shown, and may have anysuitable configuration as described herein. The disconnect mountinterface 180 has a finger interface 182 which interacts with a flexiblefinger 238 on a disconnect mount 236 on the catheter system 300, asdescribed below. Embodiments of the finger interface 182 may be in theform of a protruding finger, an interlocking feature, a groove, a slot,a window, or other similar features for releasably holding a disconnectmount 236 flexible finger 238. The distal end 102 of the implant 100 mayalso have an end cap 148. Various embodiments and combinations ofembodiments of the implant 100 may be used, including but not limited tosingle and multiple guide tube configurations, as describe above.

In some embodiments, the catheter system 300 includes a disconnect mount236 provided on the distal end 310 of a delivery catheter 302. Thedisconnect mount 236 may be any mechanical mount that releases one bodyfrom another without creating any or substantial moment arms or bendingbias. The disconnect mount 236 may provide releaseable concentrictension or concentric loading to an implant 100. The loading imparted bythe disconnect mount 236 to the implant 100 may be in a proximal ordistal direction. Distal loading may be imparted to advance the entirecatheter system 300 and implant 100 distally into a heart 5. Proximalloading may be used in conjunction with a distally-loading shaft thatworks with the disconnect mount 236 in placing an implant 100 in tensionin order to radially reduce a diameter of the implant 100. In oneembodiment, a disconnect mount 236 may include an annular ring, whichmay be controlled to switch between an expanded and a reduced diameterconfiguration. In one embodiment, the disconnect mount 236 acts like astent, such as by radially expanding or contracting. For example, thedisconnect mount 236 can include a shape memory alloy, such as nickeltitanium, which self-expands. In other embodiments, the disconnect mount236 expands under positive force, such as in response to radial forcesprovided by an inflation balloon.

The terms “concentric tension,” “concentric loading,” and “concentricforce” are broad terms intended to have their ordinary meanings. Inaddition, these terms refer to forces that are provided either in aninward or outward direction with respect to a longitudinal axis, andforces symmetrical about a longitudinal axis. Some of the symmetricalforces may be in directions with components along an axis extendingdistally or proximally along the longitudinal axis, and may also beperpendicular to the longitudinal axis. For example, in one embodiment,a disconnect mount is a generally cylindrical structure having alongitudinal axis and flexible fingers extending longitudinally from itsend. The flexible fingers are generally biased to flex inward, towardsthe longitudinal axis, or outward, away from the longitudinal axis. Thefingers are generally aligned with openings in a mating portion of theimplantable device. The openings generally extend around or within aportion of the circumference of the mating portion of the implantabledevice. As the fingers flex, they provide concentric force thatmaintains a portion of the fingers within the windows of the implantmating surface. When the fingers are engaged with the implant matingportion, proximal or distal force can thereafter be applied to theimplant with the disconnect mount to move the implant, or at least theportion of the implant coupled to the disconnect mount, in a proximal ordistal direction.

Concentric forces can be used to release the implant from a deliverysystem without applying bias to the implant, as described herein. Forexample, by concentrically releasing tension from the proximal end ofthe implant, the implant will not substantially jump, move, or otherwisechange its orientation with respect to the delivery system whenreleased.

In some embodiments, the disconnect mount includes two, three, four, ora plurality of actuating fingers, such as ten or more actuating fingers.As illustrated, the disconnect mount 236 has at least two flexiblefingers 238 which engage recesses, windows, or corresponding structurein a disconnect mount interface 180 located at the proximal end 104 ofan implant 100.

The disconnect mount 236 can be created from rod stock using acombination Swiss screw machine and Electrical Discharge Machining (EDM)operation to fashion at least two substantially symmetric flex fingers238 with protruding portions 240. The disconnect mount interface 180 mayhave a finger interface 182 that is specially adapted to releasably holda disconnect mount 236 flexible finger 238 in place. The catheter system300 has an implant actuation shaft 334 that extends through the catheterbody 302 and through the implant 100 to touch the stopping surface 126at the distal end 102 of the implant 100. When the implant actuationshaft 334 provides a sufficient load in the distal direction against thestopping surface 126 while a tensile load in a proximal direction isapplied to the proximal end 104 of the implant 100, the implant 100 canbe held in a radially-reduced configuration which overcomes the normalshape-memory bias toward a radially-expanded configuration for theimplant 100.

When the implant actuation shaft 334 is refracted proximally into thecatheter body 302, the implant 100 tends to return to itsradially-expanded configuration by moving proximally (e.g., see FIGS.17, 19, 20). When the tensile loading on the proximal end 104 of theimplant 100 is reduced by allowing the proximal end 104 of the implantto move distally, the implant 100 tends to return to itsradially-expanded configuration by moving distally (e.g., see FIGS. 18,21). The retraction of the implant actuation shaft 334 and reduction intensile loading on the proximal end 104 of the implant 100 may occurindependently, simultaneously, or incrementally to control the relativeaxial placement of the implant 100 in a LAA 10.

Still referring to FIGS. 17-20, there is illustrated various embodimentsof a disconnect mount 236 with a corresponding disconnect mountinterface 180 and a lock tube 234. The disconnect mount interface 180may have a finger interface 182 that is adapted to releasably hold adisconnect mount 236 flexible finger 238 in place. The protrudingportions 240 of the flex fingers 238 are captured within cutouts,recesses, or windows located on the finger interface 182 of thedisconnect mount interface 180, which is located on a proximal portion104 of the implantable device 100. For example, the implant's 100 fingerinterface 182 can include cutouts that releasably engage flex fingers238 of the delivery system. While the flex fingers 238 hold on to theproximal end 104 of the implant 100, an implant actuation shaft 334extends through the implant 100 and pushes distally against the distalend 102 of the implant 100. As described above, the implant 100 can bemade self-expanding, so that when the distal pushing force exerted bythe implant actuation shaft 334 or the proximal pulling (or holding)force applied by the flex fingers 238 is removed the implant 100automatically radially expands to a predetermined size and shape. Theimplant 100 can be maintained in its reduced diameter configuration byholding the proximal end 104 of the implant 100 with the flex fingers238 and pushing against the distal end 102 of the implant 100 with theimplant actuation shaft 334. In this configuration, relative movementbetween the inner implant actuation shaft 334 and the concentric, outerflex fingers 238 controls implant 100 expansion and collapse.

An embodiment of flex fingers 238 can be biased to extend eitherradially inwardly or radially outwardly. In embodiments where the flexfingers 238 are biased to extend radially inwardly, the flex fingers 238engage a disconnect mount interface 180 to lock an implant 100 to theimplant delivery system 50 when a structure prevents the flex fingers238 from extending radially inwardly. In one embodiment the flex fingers238 are held in place with a disconnect mount interface 180 of theimplant 100 by the presence of an implant actuation shaft 334 whichextends through the implant 100 and prevents the flex fingers 238 fromextending radially inwardly. When the implant actuation shaft 334 iswithdrawn proximally toward the catheter system 300 past the disconnectmount 236, the open space created by the removal of the implantactuation shaft 334 leaves room for the flex fingers 238 to extendradially inwardly under its bias. This radial movement of the flexfingers 238 releases the disconnect mount 236 from the disconnect mountinterface 180, thereby releasing the implant 100 from the implantdelivery system 50.

In embodiments where the flex fingers 238 are biased to extend radiallyoutwardly, the flex fingers 238 engage a disconnect mount interface 180to lock an implant 100 to the implant delivery system 50 in its naturalstate. When a structure or a load causes the flex fingers 238 to extendradially inwardly, the radial movement of the flex fingers 238 releasesthe disconnect mount 236 from the disconnect mount interface 180,thereby releasing the implant 100 from the implant delivery system 50.

In some embodiments, the flex fingers 238 are held in the fingerinterface 182 by a lock tube 234. The lock tube 234 can be axiallyslideable with respect to the catheter body 302 and with respect to adisconnect mount 236. In one embodiment, the lock tube 234 has athreaded portion (not illustrated) that threads into the disconnectmount 236 and extends under and between the flex fingers 238, therebypreventing the flex fingers 238 from collapsing inward (in a mannersimilar to the embodiment illustrated in FIGS. 17-18).

In another embodiment the lock tube 234 has a threaded portion (notillustrated) that threads over the disconnect mount 236 and extends overthe flex fingers 238, thereby preventing the flex fingers 238 fromexpanding outward (in a manner similar to the embodiment illustrated inFIGS. 19-20). In other embodiments, a lock tube 234 can be threaded to acatheter body 302, or a lock tube 234 may not be threaded and retainsits axial positioning with respect to a disconnect mount 236 until theuser actuates the lock tube to release the flex fingers 238. In otherembodiments, an implant actuation shaft 334 can include a protrudingfeature, such as a tab, key or pin, that engages a lock tube 234 andallows torque to be transferred from the implant actuation shaft 334 tothe lock tube 234.

FIGS. 17A-17C illustrate an embodiment of a disconnect mount 236 havingflex fingers 238, a corresponding disconnect mount interface 180, and alock tube 234 at least partially contained within a catheter body 302.In certain embodiments illustrated in FIGS. 17A-17C, the flex fingers238 can be biased to extend radially outwardly or inwardly to applyconcentric loading, as discussed above.

In one embodiment, the flex fingers 238 are biased outwardly. The flexfingers 238 can also include a proximal inclined surface 242 at thetransition from the flex finger 238 to the protruding portion 240.Referring to embodiments in FIG. 17B, after the implant 100 is deployedor radially expanded in a LAA 10 (not illustrated here), anchors 118(not illustrated here) on the implant frame 101 secure the implant 100within the LAA 10. The interface between the implant 100 and thedisconnect mount 236 provides concentric loading to the implant 100. Inone embodiment the concentric loading is concentric tension. At thispoint, the lock tube 234 can be withdrawn proximally away from contactwith the flex fingers 238, allowing the flex fingers 238 to deflectinwardly.

When the flex fingers 238 are moved proximally with respect to theimplant 100, such as when the catheter system 300 is withdrawnproximally away from the expanded implant 100 in the LAA 10, the insideedge of the disconnect mount interface 180 can press onto the proximalinclined surface 242, which provides a radially inward force to the flexfinger 238. As illustrated, the embodied disconnect mount interface 180uses a finger interface 182 in the form of an internal surface of aproximal end 104 of the implant 100. The radially inward force causesthe flex fingers 238 or at least a distal portion of the flex fingers238 to move radially inwardly.

The amount of deflection in the flex fingers 238 that effective torelease the disconnect mount 236 from the disconnect mount interface 180may depend on the thickness of the lock tube 240 alone (as isillustrated in FIG. 17B), or it may depend on the removal of the implantactuation shaft 334 proximal to the flex fingers 238 (as is illustratedin FIG. 17C) in order to release the implant 100. Once the flex fingers238 are sufficiently radially deflected, the implant 100 is disconnectedfrom the delivery system 50 without imparting any or any substantialmoment arms, bending bias, or rotational bias with respect to theimplant 100. As depicted in FIG. 17C, once the implant 100 is detached,the flex fingers 238 will bias toward their natural state (inward biasis illustrated in solid lines and outward bias is illustrated in dottedlines).

In another embodiment illustrated in FIGS. 17A-17C, the flex fingers 238are biased inwardly. Referring to embodiments in FIG. 17B, after theimplant 100 is deployed and radially expanded in a LAA, anchors on theimplant frame 101 secure the implant 100 within the LAA. The interfacebetween the implant 100 and the disconnect mount 236 provides concentricloading to the implant 100. In one embodiment the concentric loading isconcentric tension. At this point, the lock tube 234 can be withdrawnproximally away from contact with the flex fingers 238, allowing theflex fingers 238 to deflect inwardly to their natural, biased state. Theamount of deflection in the flex fingers 238 that is effective torelease the disconnect mount 236 from the disconnect mount interface 180may depend on the thickness of the lock tube 240 alone (as isillustrated in FIG. 17B), or it may depend on the removal of the implantactuation shaft 334 proximal to the flex fingers 238 (as is illustratedin FIG. 17C) in order to release the implant 100. Once the flex fingers238 are sufficiently radially deflected, the implant 100 is disconnectedfrom the delivery system 50 without imparting any or any substantialmoment arms, bending bias, or rotational bias with respect to theimplant 100. As depicted in FIG. 17C, once the implant 100 is detached,the flex fingers 238 will bias toward their natural state (inward biasis illustrated in solid lines and outward bias is illustrated in dottedlines). When the flex fingers 238 are biased inwardly, the lock tube 334can be slideably engaged under the flex fingers 238 to deflect thefingers outwardly.

In some embodiments, when the implant 100 is in its collapsedconfiguration the tension created by a load between the implantactuation shaft 334 and the flex fingers 238 may create pullout forcessufficient to cause inward flex of the flex fingers 238 and potentiallypinch underlying structure, such as the implant actuation shaft 334,which could cause the implant 100 to bind. However, the lock tube 234can prevent this from happening and can serve as a buffer between theflex fingers 238 and the underlying implant actuation shaft 334. Thisprovides smooth and uninterrupted movement of the implant actuationshaft 334 in and out of the implant 100 during expansion. It also allowsfor smooth disconnect during release of the implant 100 (“boing-less”release, or releasing without the implant “jumping”, moving, or changingits position or orientation).

In some embodiments, markers 204 are provided at locations visible underfluoroscopy or other means known in the art of visualizing themanipulation or implantation of devices within a body. The markers 204,which can be radiopaque in nature, can be placed on any surfaces toassist in deployment or recapture of an implant 100, as is describedabove for the embodiment of a marker 360 as shown in FIG. 14, whichadvantageously assists in locating the position of a distal end 344 ofan axially moveable core 342. In various embodiments, a marker 204comprises a radiopaque band, dot, coating, or material that is attachedto a disconnect mount 236, a distal end 104 of an implant 100, and aportion of an implant actuation shaft 334. Marker 204 preferably is madefrom a material readily identified after insertion into a patient's bodyby using visualization techniques that are well known to those of skillin the art. In one embodiment, the marker 204 is made from gold, ortungsten, or any such suitable material, as is well known to those ofskill in the art. In another embodiment, marker 204 is welded, soldered,or glued onto a structure for marking. In one embodiment, the use ofmarkers 204 segments is useful to discern the radial orientation of theimplant 100 within the body.

Referring to FIGS. 18A-18C, there is illustrated an embodiment of adisconnect mount 236 with flex fingers 238, a corresponding disconnectmount interface 180, and a lock tube 234 at least partially containedwithin a catheter body 302. The embodiment illustrated in FIGS. 18A-18Cis similar in many ways with the embodiment illustrated in FIGS.17A-17C, and includes many of the same components described above. Theembodiment illustrated in FIGS. 18A-18C can optionally include markers(not illustrated). The illustrated embodiment also includes a lumen 335in the implant actuation shaft 334, and lumens 150 in an end cap 148 atthe distal end 102 of the implant 100. In addition, the illustratedembodiments can be deployed in a proximal or distal direction, asdiscussed in greater detail below. Any of the features of embodimentsillustrated in FIGS. 17 and 18 can be used in conjunction with eachother, along with combinations of embodiments illustrated in FIGS.19-21, or any other embodiments of the invention described herein.

Referring to FIGS. 18A-18C, an embodiment of a catheter system 300 hasan implant actuation shaft 334 which extends through the catheter body302 and can extend through the implant 100 to touch the stopping surface126 at the distal end 102 of the implant 100. When the implant actuationshaft 334 provides a sufficient load in the distal direction against thestopping surface 126 while a proximally-directed load is applied to theproximal end 104 of the implant 100, the implant 100 can be held insufficient tension to overcome the normal shape-memory bias toward aradially-expanded configuration for the implant 100, resulting in animplant 100 with a radially-reduced configuration. The embodiment of thesystem 50 illustrated in FIGS. 17A-17C depicts steps where the implantactuation shaft 334 is retracted proximally into the catheter body 302and the implant 100 tends to return to its radially-expandedconfiguration as of its distal end 102 moving proximally.

The embodiment of the system 50 illustrated in FIGS. 18A-18C depictsteps where the concentric tensile loading on the proximal end 104 ofthe implant 100 is reduced by allowing the proximal end 104 of theimplant 100 to move distally such that the implant 100 as a whole tendsto return to its radially-expanded configuration by moving distally. Theretraction of the implant actuation shaft 334 and reduction inconcentric tensile loading on the proximal end 104 of the implant 100may occur independently, simultaneously, or incrementally to control therelative axial placement of the implant 100 in a LAA 10.

The lumen 335 in the implant actuation shaft 334 may contain radiopaqueor contrast materials injected into the catheter system 300 throughports in the deployment handle 400, as described above and below. Theexit point for contrast to exit the lumen 335 may be at the distal tipof the implant actuation shaft 334 or along any exit port (notillustrated) along the implant actuation shaft 334. One embodiment of alumen 335 is similar to the lumen 350 of the tubular torque rod 340described above and illustrated in FIG. 14. The lumen 335 preferablyallows visualization dye to flow through the lumen 335 of the implantactuation shaft 334 and through the implant frame 101 or through atleast one lumen 150 of the implant end cap 148, and into the LAA 10 (notillustrated here). Such usage of visualization dye is useful forclinical diagnosis and testing of the position of the implant 100 withinthe LAA 10 or other body openings.

FIGS. 19A-19C and 20A-20C illustrate additional embodiments of adisconnect mount 236 having flex fingers 238, a corresponding disconnectmount interface 180, and a catheter body 302, which is at leastpartially contained within a lock tube 234. The disconnect mount 236provides concentric loading to the implant 100 without impartingrotational loads to the implant 100. The flex fingers 238 can be biasedto extend radially outwardly or inwardly, as discussed above. In oneembodiment, the flex fingers 238 are biased inwardly. The flex fingers238 can also include a proximal inclined surface 242 at the transitionfrom the flex finger 238 to the protruding portion 240. As illustrated,the embodied disconnect mount interface 180 uses a finger interface 182in the form of slots or windows in a wall of a proximal end 104 of theimplant 100. Referring to embodiments in FIGS. 19B and 20B, after theimplant 100 is deployed and radially expanded in a LAA 10 (notillustrated here), anchors 118 (not illustrated here) on the implantframe 101 secure the implant 100 within the LAA 10. The interfacebetween the implant 100 and the disconnect mount 236 provides concentricloading to the implant 100. In one embodiment the concentric loading isconcentric tension.

The lock tube 234 can be withdrawn proximally away from contact with theflex fingers 238, allowing the flex fingers 238 to deflect outwardly.When the flex fingers 238 are moved proximally with respect to theimplant 100, such as when the catheter system 300 is withdrawnproximally away from the expanded implant 100 in the LAA 10, the insideedge of the disconnect mount interface 180 can press onto the proximalinclined surface 242, which provides a radially outward force to theflex fingers 238. The radially outward force causes the flex fingers 238or at least a distal portion of the flex fingers 238 to move radiallyoutwardly. Once the flex fingers 238 are sufficiently radiallydeflected, the implant 100 is disconnected from the delivery system 50without imparting any or any substantial moment arms or bending biaswith respect to the implant 100. As depicted in FIGS. 19C and 20C, oncethe implant 100 is detached, the flex fingers 238 will bias toward theirnatural state (inward bias is illustrated in solid lines and outwardbias is illustrated in dotted lines).

In another embodiment illustrated in FIGS. 19A-19C and 20A-20C, the flexfingers 238 are biased outwardly. Referring to embodiments in FIGS. 19Band 20B, after the implant 100 is deployed and radially expanded in aLAA, anchors (not illustrated) on the implant frame 101 secure theimplant 100 within the LAA. The interface between the implant 100 andthe disconnect mount 236 provides concentric loading to the implant 100.In one embodiment the concentric loading is concentric tension. At thispoint, the lock tube 234 can be withdrawn proximally away from contactwith the flex fingers 238, allowing the flex fingers 238 to deflectoutwardly in their natural state.

Once the flex fingers 238 are sufficiently radially deflected, theimplant 100 is disconnected from the delivery system 50 withoutimparting any or any substantial moment arms or bending bias withrespect to the implant 100. As depicted in FIGS. 19C and 20C, once theimplant 100 is detached, the flex fingers 238 will bias toward theirnatural state (inward bias is illustrated in solid lines and outwardbias is illustrated in dotted lines). When the flex fingers 238 arebiased outwardly, the lock tube 334 can be slideably engaged over theflex fingers 238 (not illustrated in FIG. 19C) or over a finger pivotaxis 239 (as illustrated in FIG. 20C) in order to deflect the flexfingers 238 inwardly to facilitate extraction of the implant deliverysystem and/or catheter system from the body.

FIGS. 20A-20C illustrate an embodiment of a disconnect mount 236 withflex fingers 238, a corresponding disconnect mount interface 180, and acatheter body 302 at least partially contained within a lock tube 234,as described above. The illustrated embodiment of FIGS. 20A-20C includesa lock tube 234 that only partially surrounds the flex fingers 238 ofthe disconnect mount 236. In addition, a finger pivot axis 239 locatedproximally to the flex fingers 238 defines the axis about which the flexfingers rotate. In leaving the lock tube 234 proximal to the flexfingers 238 and at least a portion of the disconnect mount 236, the locktube 234 can maintain a relatively smaller lock tube 234 diameter thanwould be the case if the lock tube 234 had to enclose the entirediameter of the disconnect mount 236, resulting in easier insertion ofthe catheter system 300 into the body. The finger pivot axis 239 can beformed as a crease in an extended flex finger 238 located proximally toan increase in disconnect mount 236 diameter, or as a physical hinge orpin in a linkage mechanism to create the disconnect mount 236.

All of the foregoing embodiments, including those of FIGS. 17A-20C couldinclude an implant that has a single or dual guide tubes, as discussedabove. For example, in the embodiments of FIGS. 17A-20C, the implant 100could include a distal, outer guide tube attached to the distal end 102of the implant 100, and a concentric, proximal, inner guide tubeattached to the proximal end 104 of the implant 100.

FIGS. 21A-21C illustrate another embodiment of a distal portion of animplant delivery system 50, which includes an implant 100, an implantrelease and recapture mechanism 200, a catheter system 300, and adeployment handle 400 (not illustrated). The illustrated embodimentsinclude an implant 100 that has a proximal end 104, a distal end 102with a stopping surface 126, a frame 101, tissue anchors 118, and adisconnect mount interface 180 on the proximal end 104 of the implant100. The disconnect mount interface 180 has a finger interface 182 whichinteracts with a flexible finger 238 on a disconnect mount 236 on thecatheter system 300 to apply releasable concentric loads in a mannersimilar to the embodiments described above. Embodiments of the fingerinterface 182 may be in the form of a protruding finger, an interlockingfeature, a groove, a slot, a window, or other similar features forreleasably holding, engaging and/or coupling a disconnect mount flexiblefinger 238. The distal end 102 of the implant 100 may also have an endcap 148 with zero or more lumens 150. Various embodiments andcombinations of embodiments of the implant 100 may be used, includingbut not limited to single or multiple guide tube configurations, asdescribed above.

As illustrated, FIGS. 21A-21C show an implant with a multiple guide tubeconfiguration as is described above relating to FIGS. 13A and 13B. Theimplant 100 has an outer guide tube 162 which is also a distal guidetube 130, and an inner guide tube 164 which is also a proximal guidetube 160.

In some embodiments the catheter system 300 has a disconnect mount 236provided on the distal end 310 of a delivery catheter 302. Thedisconnect mount 236 may be any mechanical mount that releases one bodyfrom another without creating any or any substantial moment arms orbending bias. The disconnect mount 236 may provide releaseableconcentric tension or concentric loading to an implant 100. The loadingimparted by the disconnect mount 236 to the implant 100 may be in aproximal or distal direction. For example, in some embodiments, theconcentric loading applies tension in a proximal direction with respectto the implant, and in other embodiments, the concentric loading appliesa pushing force in a distal direction.

Distal loading may be imparted to advance the entire catheter system 300and implant 100 distally into a heart. Proximal loading may be used inconjunction with a distally-loading shaft that works with the disconnectmount 236 in placing an implant 100 in tension in order to radiallyreduce a diameter of the implant 100. In one embodiment, a disconnectmount 236 includes an annular ring that is controlled to switch betweenan expanded and a reduced diameter configuration. In one embodiment, thedisconnect mount 236 may act like a stent, and radially expand whenactivated.

In other embodiments, a disconnect mount includes two, three, four, or aplurality of actuating fingers, such as ten or more actuating fingers.As illustrated, the disconnect mount 236 has at least two flexiblefingers 238 which may engage within recesses, windows, or correspondingstructure in a disconnect mount interface 180 on a proximal end 104 ofan implant 100. The disconnect mount interface 180 may have a fingerinterface 182 that is specially adapted to releasably hold a disconnectmount 236 flexible finger 238 in place.

The disconnect mount 236 can be created from rod stock using acombination Swiss screw machine and Electrical Discharge Machining (EDM)operation to fashion at least two substantially symmetric flex fingers238 with protruding portions 240. The disconnect mount interface 180 mayhave a finger interface 182 that is specially adapted to releasably holda disconnect mount 236 flexible finger 238 in place.

The protruding portions 240 of the flex fingers 238 are captured withincutouts, recesses, or windows located on the finger interface 182 of thedisconnect mount interface 180, which is located on a proximal portion104 of the implantable device 100. For example, the implant's fingerinterface 182 can include cutouts that releasably engage flex fingers238 of the delivery system 50.

In some embodiments, the catheter system 300 has an implant actuationshaft 334 which extends through the catheter body 302 and can extendthrough the implant 100 to touch the stopping surface 126 at the distalend 102 of the implant 100. When the implant actuation shaft 334provides a sufficient load in the distal direction against the stoppingsurface 126 while a tensile load in a proximal direction is applied tothe proximal end 104 of the implant 100, the implant 100 can be held ina radially-reduced configuration. This overcomes the shape-memory biastoward a radially-expanded configuration for the implant 100.

When the implant actuation shaft 334 is refracted proximally into thecatheter body 302, the implant 100 tends to return to itsradially-expanded configuration by moving proximally. When the tensileloading on the proximal end 104 of the implant 100 is reduced byallowing the proximal end 104 of the implant to move distally, theimplant 100 tends to return to its radially-expanded configuration bymoving distally (as is depicted in the embodiment illustrated in FIGS.21A-21C). The refraction of the implant actuation shaft 334 andreduction in tensile loading on the proximal end 104 of the implant 100may occur independently, simultaneously, or incrementally to control therelative axial placement of the implant 100 in a LAA 10.

In some embodiments, a lumen 335 (not illustrated) in the implantactuation shaft 334 may contain radiopaque or contrast materialsinjected into the catheter system 300 through ports in the deploymenthandle 400, as described above and below. In some embodiments, theimplant actuation shaft 334 may be constructed of a flexible material,such as a puzzle lock profile 600, as described relating to FIG. 25Abelow.

In the illustrated embodiment of FIGS. 21A-21C, the implant actuationshaft 334 includes a threaded portion 336. In this embodiment, anyrotational loads imparted due to the threadable engagement between thehub 236 and the implant actuation shaft 334 are transferred within theimplant release and recapture mechanism 200 on the side with thecatheter system 300, thereby avoiding rotational loading of the implant100 within the LAA 10.

The threaded portion 336 of the implant actuation shaft 334 may bemanufactured by a lathing or machining process from the same material asthe implant actuation shaft 334, or threaded portion 336 may be aseparate piece that is bonded, welded, soldered, braided, or otherwiseattached to a portion of the implant actuation shaft 334. In theillustrated embodiment, rotating the implant actuation shaft 334 causesit to advance longitudinally. For example, the threaded portion 336engages a threaded portion 246 of a disconnect mount 236 in a screw-likemanner. Rotating the implant actuation shaft 334 when the threadedportions 336, 246 are engaged causes the shaft 334 to advance proximallyor distally, depending upon the direction of shaft rotation. When thethreads are disengaged, the actuation shaft 334 can slide with respectto the implant 100.

The illustrated embodiment can provide anywhere in the range of 0%-100%of the collapse of the implant 100 by axially sliding a implantactuation shaft 334. In some embodiments, the implant actuation shaft334 causes 25%, 30%, 40%, 50%, 60%, 70%, 75%, 80%, 90%, or 95% of thecollapse or expansion of the implant 100, and can lock the implant in apartially-expanded or partially-reduced state. This provides theadvantage of allowing the clinician to verify proper position andorientation of the implant 100 in small steps as the implant 100 isdeployed within the patient's body.

Expansion of the implant 100 occurs while the threaded portion 336 ofthe implant actuation shaft 334 is engaged with the threaded portion 246the disconnect mount 236. While the threaded portion 336 of the implantactuation shaft 334 is engaged with the threaded portion 246 thedisconnect mount 236, the implant actuation shaft 334 is essentiallylocked in place unless sufficient torque is provided to rotate the twothreaded portions 336 and 246 with respect to one another. This allowsthe implant 100 to be held or maintained in a fully or partiallyradially-reduced configuration.

While the flex fingers 238 hold the proximal end 104 of the implant 100with concentric tensile force, an implant actuation shaft 334 extendsthrough the implant 100 and pushes distally against the distal end 102of the implant 100. As described above, the implant 100 can be madeself-expanding, so that when the distal pushing force exerted by theimplant actuation shaft 334 or the concentric proximal pulling (orholding) force applied by the flex fingers 238 is removed or reduced theimplant 100 automatically radially expands to a predetermined size andshape. The implant 100 can be maintained in its reduced diameterconfiguration by holding the proximal end 104 of the implant 100 withthe flex fingers 238 and pushing against the distal end 102 of theimplant 100 with the implant actuation shaft 334. In this configuration,relative movement between the inner implant actuation shaft 334 and theconcentric, outer flex fingers 238 controls implant 100 expansion andcollapse.

In some embodiments, the flex fingers 238 are biased to extend eitherradially inwardly or radially outwardly. In embodiments where the flexfingers 238 are biased to extend radially inwardly, the flex fingers 238engage a disconnect mount interface 180 to lock an implant 100 to theimplant delivery system 50 when a structure prevents the flex fingers238 from extending radially inwardly.

In one embodiment, as illustrated in FIGS. 21A-21C, the flex fingers 238may be held in place with a disconnect mount interface 180 of theimplant 100 by the presence of an implant actuation shaft 334 whichextends through the implant 100 and prevents the flex fingers 238 fromextending radially inwardly. When the implant actuation shaft 334 iswithdrawn proximally toward the catheter system 300 past the disconnectmount 236, the open space created by the removal of the implantactuation shaft 334 leaves room for the flex fingers 238 to extendradially inwardly under its bias. This radial movement of the flexfingers 238 releases the disconnect mount 236 from the disconnect mountinterface 180, thereby releasing the implant 100 from the implantdelivery system 50.

In embodiments where the flex fingers 238 are biased to extend radiallyoutwardly, the flex fingers 238 engage a disconnect mount interface 180to lock an implant 100 to the implant delivery system 50 in its naturalstate. When a structure or a load causes the flex fingers 238 to extendradially inwardly the radial movement of the flex fingers 238 releasesthe disconnect mount 236 from the disconnect mount interface 180,thereby releasing the implant 100 from the implant delivery system 50with significantly reduced or non-existent bending bias and rotationalbias.

In some embodiments of an implant delivery system 50, markers 204 (notillustrated) may be placed in locations visible by fluoroscopic or othermeans known in the art of visualizing the manipulation or implantationof devices within a body. The markers 204, which can be radiopaque innature, can be placed on any surfaces to assist in deployment orrecapture of an implant 100, as is described above for the embodiment ofa marker 360 as shown in FIG. 14, which advantageously assists inlocating the position of a distal end 344 of an axially moveable core342.

In various embodiments, a marker 204 comprises a radiopaque band, dot,coating, or material that is attached to a disconnect mount 236, adistal end 104 of an implant 100, and a portion of an implant actuationshaft 334. Marker 204 preferably is made from a material readilyidentified after insertion into a patient's body by using visualizationtechniques that are well known to those of skill in the art. In oneembodiment, the marker 204 is made from gold, or tungsten, or any suchsuitable material, as is well known to those of skill in the art. Inanother embodiment, marker 204 is welded, soldered, or glued onto astructure for marking. In one embodiment, the use of markers 204segments is useful to discern the radial orientation of the implant 100within the body.

Referring once again to FIGS. 21A-21C, flex fingers 238 can be biased toextend radially outwardly or inwardly, as discussed above. In oneembodiment, the flex fingers 238 are biased outwardly. The flex fingers238 can also include a proximal inclined surface 242 at the transitionfrom the flex finger 238 to the protruding portion 240. As illustrated,the embodied disconnect mount interface 180 uses a finger interface 182in the form of slots or windows in a wall of a proximal end 104 of theimplant 100.

Referring to embodiments in FIG. 21B, after the implant 100 is deployedand radially expanded in a LAA 10 (not illustrated here), anchors 118 onthe implant frame 101 secure the implant 100 within the LAA 10. Asdepicted in FIG. 21C, the implant actuation shaft 334 can be withdrawnproximally away from contact with the flex fingers 238, allowing theflex fingers 238 to deflect inwardly. When the flex fingers 238 aremoved proximally with respect to the implant 100, such as when thecatheter system 300 is withdrawn proximally away from the expandedimplant 100 in the LAA 10, the inside edge of the disconnect mountinterface 180 can press onto the proximal inclined surface 242 (notshown), which provides a radially inward force to the flex fingers 238.

The radially inward force causes the flex fingers 238 or at least adistal portion of the flex fingers 238 to move radially inwardly. Oncethe flex fingers 238 are sufficiently radially deflected, the implant100 is disconnected from the delivery system 50 without imparting any orany substantial moment arms or bending bias with respect to the implant100. As depicted in FIG. 21C, once the implant 100 is detached, the flexfingers 238 will bias toward their natural state (inward bias isillustrated in solid lines and outward bias is illustrated in dottedlines).

In another embodiment illustrated in FIGS. 21A-21C, the flex fingers 238are biased inwardly. Referring to embodiments in FIG. 21B, after theimplant 100 is deployed and radially expanded in a LAA 10 (notillustrated here), anchors 118 on the implant frame 101 secure theimplant 100 within the LAA 10. As depicted in FIG. 21C, the implantactuation shaft 334 can be withdrawn proximally away from contact withthe flex fingers 238, allowing the flex fingers 238 to deflect inwardlyin their natural state. Once the flex fingers 238 are sufficientlyradially deflected, the implant 100 is disconnected from the deliverysystem 50 without imparting any moment aims or bending bias with respectto the implant 100. As depicted in FIG. 21C, once the implant 100 isdetached, the flex fingers 238 will bias toward their natural state(inward bias is illustrated in solid lines and outward bias isillustrated in dotted lines). When the flex fingers 238 are biasedinwardly, the implant actuation shaft 334 can be slideably engaged underthe flex fingers 238 in order to deflect the flex fingers 238 outwardly.

As illustrated in FIGS. 21A-C, some embodiments include a flexible sock392 positioned between the catheter body 302 and the disconnect mount236. The sock 392 is discussed in greater detail below. In someembodiments, a catheter body 302 may be directly mounted to a disconnectmount 236.

In the illustrated embodiments described herein, an implant deploymentsystem generally includes an implant coupled to a catheter with arelease mechanism. The system also generally includes a mechanism toexpand or contract the diameter of the implant. Although many of theembodiments describe the release mechanism coupled to the distal end ofthe catheter and the proximal end of the implant, it should be wellunderstood by those of skill in the art that in other embodiments, therelease mechanism is coupled to the distal end of the implant.

In addition, when the release mechanism is coupled to the proximal endof the implant, the implant is expanded by either moving the distal endof the implant proximally, by moving the proximal end of the implantdistally, or by moving both ends towards the center of the implant. Inmany cases, the proximal end of the implant is held in place withrespect to the patient's LAA and the distal end of the implant isallowed to move proximally under the self-expanding forces of theimplant. However, in some situations, for example when treating patientsthat have a very short LAA, it may be desirable to perform a differentprocedure. For example, in such situations the clinician may desire tohold the distal end of the implant in place with respect to thepatient's LAA while moving the proximal end of the implant distally;otherwise, the proximal end of the implant could wind up positionedwithin the patient's left atrium.

In some embodiments, the implant is expanded “in a distal direction” asjust described by coupling the release mechanism to the distal end ofthe implant and then releasing tension from the implant's proximal end.Once the implant is radially expanded, the implant is released and thecatheter is removed. For example, in one embodiment, the catheter and/orrelease mechanism extends through the implant's proximal end and itsbody to contact a portion near the distal end of the implant from withinthe implant.

The term “in a distal direction” refers to the steps of keeping thedistal end of the implant in a relatively, substantially fixed positionwith respect to the deployment site while advancing the proximal end ofthe implant distally. Similarly, the term “in a proximal direction”refers to the steps of holding the proximal end of the implant in arelatively, substantially fixed position with respect to the deploymentsite while advancing the distal end of the implant proximally.

Therefore, the deployment systems can be configured to deploy in aproximal or a distal direction (or both). In addition, for anydeployment direction configuration, the deployment systems can befurther configured such that the release mechanism couples to either theproximal or distal end of the implant.

Referring to FIGS. 21D and 21E, in one embodiment the deployment system50 is configured to deploy the implant 100 in a distal direction, andthe release mechanism 200 is coupled to the proximal end 104 of theimplant 100. A shaft, such as an axially moveable core 304, extendsthrough the implant 100 and contacts the distal end 102 of the implant100. The core 304 includes an inner core 305 and an outer core 307,which are coaxially aligned and can be longitudinally moved with respectto each other.

The outer core 307 includes two longitudinally spaced lockingmechanisms. The first locking mechanism 309 is configured to engage andsecure the outer core 307 to a mating portion 313 of the distal end 310of the catheter 302. The second locking mechanism 311 is configured toengage and secure the outer core 307 to a mating portion 345 of theimplant 100. In one embodiment, the locking mechanisms 309 and 311include two radially offset cams 347 and 349 configured to engage matingsurface slots 351 and 353, respectively, extending annularly withincorresponding catheter mating portion 313 and implant mating portion345, respectively.

Initially the cams 347 and 349 of the outer core 307 engage and arelocked within both the catheter mating portion 313 and implant matingportion 345, respectively. In this configuration, the catheter 302,outer core 307, and implant 100 are fixed with respect to each other,and can be advanced together through a deployment sheath, such as atransseptal sheath (not illustrated here) or other retractable sheath.

The inner core 305 is extended to contact and push against the distalend 102 of the implant 100. Pushing on the distal surface 126 at thedistal end 102 with the inner core 305 while holding the proximal end104 in tension with the outer core 307 maintains the implant 100 in areduced-diameter configuration. The diameter-reduced implant 100 isadvanced through the patient's vasculature to a desired deployment site.At the deployment site, the implant's 100 distal end 102 is positionedunder visualization at a desired location.

The outer core 307 is rotated with respect to the catheter 302 to causethe catheter cam 347 to align with an exit slot 355 in the cathetermating portion 313. Because the catheter cam 347 and implant cam 349 areoffset from one another, alignment of the first cam 347 with thecatheter mating portion's 313 exit slot 355 does not cause the secondcam 349 to be aligned with the implant mating portion's 345 exit slot357. For example, in some embodiments, the cams 347 and 349 are offsetby about 15, 45, or 90 degrees from each other.

The outer core 307 is then advanced distally with respect to thecatheter 302. The outer core 307 is now axially decoupled from thecatheter 302, but still coupled to the proximal end of the implant 100via the second cam 349-mating portion 345 engagement. As the outer core307 is moved distally, the proximal end 104 of the implant 100 is alsoadvanced distally. This causes the implant 100 to expand in a distaldirection, e.g., while maintaining the distal end 102 of the implant 100in a substantially fixed position with respect to the deployment site(e.g., the LAA 10, not pictured here). In addition, as the outer core307 is advanced distally with respect to the catheter 302, the outercore 307 is also advanced distally with respect to the inner core 305.This prevents distal advancement of the outer core 307 from pushing theimplant 100 deeper into the LAA 10, or out of the desired deploymentlocation.

When the implant 100 is fully expanded the outer core 307 is disengaged,or decoupled from the implant 100 by rotating the second cam 349 withrespect to the implant 100. When the implant cam 349, or a cam tab, isaligned with an exit slot 357 in the implant mating portion 345, theouter core 307 can be retracted proximally with respect to the implant100 without substantially affecting the implant's 100 deploymentlocation or orientation. At this point the outer core 307 is decoupledfrom both the catheter 302 and implant 100, and may withdrawn with thecatheter 302 and inner core 305 from the patient's vasculature.

In some embodiments the inner 305 and outer shafts 307 are made fromflexible hypotube. In other embodiments, the locking mechanisms 309 and311 are sometimes referred to as an implant key or tip or as a catheterkey or tip. The mating portion 313 of the catheter 302 is sometimesreferred to as the locking tip.

FIG. 21F illustrates another flexible implant delivery system inaccordance with yet another embodiment of the invention. The deliverysystem 50 includes an implantable device 100 and a release mechanism200. The configuration described with respect to FIG. 21F can beutilized and/or incorporated into any of the other embodiments describedherein.

The implantable device 100 is similar to all of the other implantabledevices described herein. The implantable device 100 is configured toexpand from a radially reduced configuration to a radially expandedconfiguration. For example, in some embodiments, the implantable device100 is self expandable. The implantable device 100 includes a pluralityof struts that extend from the implant's proximal end 104 to its distalend 102. A window, notch, hole, or port, in the implant's proximal end104 is configured to releasably engage the release mechanism 200.

The release mechanism 200 includes a drive shaft 363, which is coupledat its distal end to the proximal end of a flexible recapture shaft 365.In one embodiment, the drive shaft 363 is made from 0.025″ diametertubing. In another embodiment, the flexible recapture shaft 365 is madefrom 0.042″ outside diameter by 0.027″ inside diameter tubing. Thedistal end of the flexible recapture shaft 365 is coupled to a threadedadapter 337. In one embodiment, the recapture shaft 365 and adapter 337are coupled with a cross pin 338. For example, a 0.025″ cross pin 338 issometimes used. The distal end of the threaded adapter 337 is coupled toa second flexible recapture shaft 367. In some embodiments, a singleflexible recapture shaft 365 is used, which extends through the threadedadapter 337. The threaded adapter 337 includes a threaded portion 339with threads along at least a portion of its outside surface.

The driver 363, flexible recapture shafts 365 and 367, and threadedadapter 337 are disposed within an outer shaft assembly 369. The outershaft assembly 369 includes a braided shaft 371 that is coupled at itsdistal end to a flexible torque shaft 375. In one embodiment, thebraided shaft 371 is the braided sock 392 described above. In anotherembodiment, the braided shaft 371 has dimensions of 0.084″OD.times.0.055″ ID. In one embodiment, the flexible torque shaft 375 isthe braided sock 392 described above. In one embodiment, the flexibletorque shaft 375 has dimension of 0.083″ OD.times.0.072″ ID. The distalend of the flexible torque shaft 375 is coupled to a push screwdisconnect 377, which in some embodiments is the disconnect mount 236described in greater detail herein.

The push screw disconnect 377 has distally extending fingers 379 thathave a larger diameter at their distal ends. The push screw disconnect377 also includes a threaded inside surface 381 configured to engage thethreaded portion 339 of the threaded adapter 337. The distal ends of thefingers 379 are configured to engage the window 182 in the implant 100and to hold the implant 100 with respect to the braided shaft 371 andflexible torque shaft 375. However, in one embodiment the fingers 379are biased to flex inward to release the implant 100. Therefore, aninner core assembly 361, comprising the driver 363, flexible recaptureshafts 365 and 367, and threaded adapter 337 are used to interfere withinward movement of the fingers 379, and to hold the fingers 379 outwardsuch that they continue to radially, coaxially engage the implant 100.

To release the implant 100, the inner core assembly 361 is rotated withrespect to the push screw disconnect 377. The core assembly 361 isrotated until it no longer engages the push screw disconnect 377, atwhich point it is retracted proximally with respect to the outer shaftassembly 369. Once the inner core assembly 361 is retracted, the fingers379 move radially and concentrically inward to their biased position,thereby releasing the implant 100. The implant 100 is released byremoving the concentric radial force provided by the outer core assembly369. Releasing the implant 100 in this manner does not cause the implant100 to substantially jump, move, or otherwise change its orientationwith respect to the delivery system 50.

3. Deployment Catheter and Deployment Handle

Referring again to FIG. 2, there is illustrated a block diagramrepresenting an implant delivery system 50 suitable for use with any andall of the embodiments discussed herein. The implant delivery system 50includes an implant 100, an implant release and recapture mechanism 200,a catheter system 300 and a deployment handle 400. FIG. 2A illustratesone embodiment of an implant delivery system 50 comprising particularexamples of an implant 100, an implant release and recapture mechanism200, a catheter system 300 and a deployment handle 400.

Referring again to FIG. 11, there is schematically illustrated a furtherembodiment of the present invention. An adjustable implant deliverysystem 50 comprises generally a catheter 302 for placing a detachableimplant 100 within a body cavity or lumen, as has been discussed. Thecatheter 302 comprises an elongate flexible tubular body 306, extendingbetween a proximal end 308 and a distal end 310. The catheter is shownin highly schematic form, for the purpose of illustrating the functionalaspects thereof. The catheter body will have a sufficient length anddiameter to permit percutaneous entry into the vascular system, andtransluminal advancement through the vascular system to the desireddeployment site. For example, in an embodiment intended for access atthe femoral vein and deployment within the left atrial appendage, thecatheter 302 will have a length within the range of from about 50 cm toabout 150 cm, and a diameter of generally no more than about 15 French.Further dimensions and physical characteristics of catheters fornavigation to particular sites within the body are well understood inthe art and will not be further described herein.

The tubular body 306 is further provided with a handle 402 generally onthe proximal end 308 of the catheter 302. The handle 402 permitsmanipulation of the various aspects of the implant delivery system 50,as will be discussed below. Handle 402 may be manufactured in any of avariety of ways, typically by injection molding or otherwise forming ahandpiece for single-hand operation, using materials and constructiontechniques well known in the medical device arts.

In the embodiment illustrated in FIG. 14, or any other of the deploymentand/or removal catheters described herein, the distal end 310 of thetubular body 306 may be provided with a zone or point of enhancedlateral flexibility (indicated by the sectional lines on the tube 306 atthe distal end 310). This may be desirable in order allow the implant toseat in the optimal orientation within the left atrial appendage 10, andnot be restrained by a lack of flexibility in the tubular body 306. Thismay be accomplished in any of a variety of ways, such as providing thedistal most one or two or three centimeters or more of the tubular body306 with a spring coil configuration. In this manner, the distal end ofthe tubular body 306 will be sufficiently flexible to allow the implant100 to properly seat within the LAA 10. This distal flex zone on thetubular body 306 may be provided in any of a variety of ways, such as bycutting a spiral slot in the distal end of the tubular body 306 usinglaser cutting or other cutting techniques. The components within thetubular body 306 such as torque rod 340 may similarly be provided with azone of enhanced flexibility in the distal region of the tubular body306.

FIG. 22 (which is similar to FIG. 2A) illustrates one embodiment of animplant delivery system 50 comprising an operably connected implant 100,an implant release and recapture mechanism 200, a catheter system 300and a deployment handle 400. As shown in FIG. 22, the embodied cathetersystem 300 comprises a peel-away sheath 314, a recapture sheath 522, adeployment catheter 302, a loading collar 323, a multi-lumen shaft 326,and an axially moveable core 304, each described further below. Thesystem 50 may also include a transseptal sheath 520 (not illustratedhere) that is substantially coaxial and external to the other catheters.In some embodiments, the transseptal sheath may be one of the othercatheters. The deployment handle 400 comprises a handle 402, a controlknob 408, a release knob 410, a proximal injection port 412 and a distalinjection port 414. Injection ports 546, 548, as shown in FIG. 22,preferably are provided in the delivery system 50 to allow contrastinjection proximally and distally of the implant 100 to facilitatein-vivo assessment of the positioning and seal quality of the implant100.

Referring again to FIG. 22, illustrated is an embodiment of an implantdelivery system 50. When an embodiment of the delivery system 50 isassembled, a recapture sheath 522 is loaded over the deployment catheter302, distal to the handle 402. The recapture sheath 522 is designed toallow recapture of the implant 100 prior to its detachment or finalrelease, such as described with respect to retrieval catheter 502 above.Recapture petals or flares 510 may be provided on the distal end 506 ofthe recapture sheath 522 to cover the anchors 118 of the implant 100during retrieval into the transseptal sheath 520, as described abovewith respect to FIGS. 15C-15E, and further below. A Touhy-Borst adapteror valve 530 may be attached to the proximal end 524 of the recapturesheath 522. The recapture sheath 522 comprises a radiopaque marker 528on its distal end 526 near the recapture flares 510. The recapturesheath 522 comprises a recapture sheath injection port 529 fordelivering fluid proximal the implant 100.

An embodiment of the peel-away sheath 314 is provided over a portion ofthe recapture sheath 522, between Touhy-Borst valve 530 and recaptureflares 510. The peel-away sheath 314 is used to introduce a catheter 302into a transseptal sheath 520 (not illustrated). As shown in FIG. 22, anembodiment of the peel-away sheath 314 comprises a locking collar 315, apeel-away section 316, and a reinforced section 317. The locking collarcan be unlocked relative to peel-away section 316, and may include athreaded hub 318 that releasably engages tabs 319 of the peel-awaysection 316.

An embodiment of the loading collar 323 is located over a portion of thepeel-away sheath 314 and a portion of the recapture sheath 522 with itsproximal end being located over the peel-away sheath 314 at its distalend loaded over recapture sheath 522. The loading collar 323 canaccommodate loading a collapsed implant 100 into the peel-away sheath314 as described below. As shown in FIG. 17, an embodiment of theloading collar 323 comprises a first end portion 324 adapted to receiveand extend over a collapsed implant 100, and a second end portion 325configured to guide the collapsed implant 100 into the peel-away sheath314. The loading collar 323 may be made of stainless steel.

In order to assemble an embodiment of the delivery system 50, theaxially movable core 304 and control line 312 are fed into themulti-lumen shaft 326 of the deployment catheter 302. The multi-lumenshaft 326 is then coupled with components of the deployment handle 400and the injection port components 412, 414. The peel-away sheath 314 andthe loading collar 323 are slid onto the recapture sheath 522, and therecapture sheath 522 is slid onto the deployment catheter 302. Theimplant 100 is then loaded on an end of the axially movable core 304 andcoupled with the control line 312. In one embodiment, the implant 100 isloaded on an end of the axially movable core 304 by screwing the axiallymovable core 304 into the threaded portion 246 of a disconnect mount 236(not illustrated here). The control knob 408 and outer casing of thedeployment handle 400 are then coupled with the system.

In an embodiment of the deployment catheter system 300, a catheter 302is used in connection with a transseptal sheath 520 (not illustratedhere, but see FIG. 25) to advance the implant 100 for deployment in apatient. The transseptal sheath 520 is a tubular device that in oneembodiment can be advanced over a guidewire (not shown) for accessingthe LAA 10 of a patient's heart 5. In some embodiments the transseptalsheath 520 may also serve as one of the other disclosed cathetersdescribed herein. Transseptal sheath 520 in some embodiments has apermanent bend or a controllable bend. A hemostasis valve (notillustrated) is provided at the proximal end of transseptal sheath. Afluid injection port is also provided at the proximal end to deliveryfluid such as contrast media through the transseptal sheath. Systems andmethods for implanting the device 100 in the LAA 10 are describedfurther below.

One embodiment of a multi-lumen shaft 326 may comprise a four-lumenshaft as illustrated in FIG. 22A. The multi-lumen shaft 326 comprises acore lumen 328 for holding an axially moveable core 304, a control linelumen 330 and two proximal injection lumens 332 in communication withproximal injection port 412. In some embodiments, the axially moveablecore 304 is the implant activation shaft 334, discussed in greaterdetail above.

An axially moveable core 304 preferably extends from the deploymenthandle 400 through the core lumen 328 of the catheter 302 and couplesthe implant 100 of the delivery system 50. A control line 312 (referredto previously as a pull wire 312) preferably extends through the controlline lumen 330 and preferably couples a proximal hub 104 of the implant100 to the deployment handle control knob 408, allowing for implant 100expansion and collapse. The control line 312 preferably extends around aportion of the axially movable core 304 near the proximal hub 104 of theimplant 100, and is coupled to the implant 100 by crosspin 146, asdescribed above.

Referring to FIG. 23, one embodiment of the catheter system 300preferably comprises a flexible catheter section 362 at its distal end,which in some embodiments is a spiral cut tubular section housed in apolymer sleeve 366. The flexible catheter section 362 may be coupled toa distal end of a multi-lumen shaft 326.

As shown in FIGS. 24 and 24A, one embodiment of the axially moveablecore 304 preferably includes a hollow proximal shaft 368 and a hollowdistal shaft 370 with a flexible hollow core section 372 therebetween,all co-axially aligned and connected. In one embodiment, the proximalend of the distal shaft 370 is attached to the distal end of theflexible core section 372, and the proximal end of the flexible coresection 372 is attached to the distal end of the proximal shaft 368. Insome embodiments, the flexible core section 372 has a spring coilsection 374 housed in a polymer sleeve 376, the spring coil section 374preferably coupled with the shafts 368 and 370 on first and second ends378 and 380, respectively. In another embodiment an injection tube 373with a lumen is provided, through which contrast fluid may be ejectedout of the distal end of the implant actuation shaft 334 and into theimplant 100. This is useful in assessing implant seal against the ostiumor inside wall of the left atrial appendage. The injection tube 373 hasbeen prototyped in low durometer (flexible) PEBAX and provides a softsegment transition over the distal-most 10 cm of the delivery catheter302 or within a flexible core section 372. The injection tube 373 may beconnected to other tubes such as a lock tube 234 (as discussed relatingto FIGS. 17-20) but is not used to torque or apply rotational forces tothe tube.

The axially moveable core 304 preferably is disposed within thedeployment catheter 302 such that the flexible core section 372 may belinearly co-located with the flexible catheter section 362 at a distalportion 382 of the catheter system 300 during appropriate times during aprocedure, as shown in FIG. 23. When the flexible core section 372 isaligned and linearly co-located with the flexible catheter section 362,the sections preferably cooperate to form a delivery system flexiblesegment 384. As shown in FIGS. 22 and 23, the delivery system flexiblesegment 384 preferably is located toward a distal portion 382 of thecatheter system 300.

In one embodiment, shown in FIG. 24, the distal shaft 370, flexible coresection 372, and proximal shaft 368 are attached by welding. Smallwindows 386 may be provided to allow welding materials to flow betweenthe shafts 564, 576 and 578 and provide stronger bonding therebetween.In another embodiment, solder, glue, or press-fitting is used to attachshafts 564, 576, and 578 to one another, as is well known to those ofskill in the art. In another embodiment, the shafts 564, 576 and 578 areformed from a single tube, for example, a laser-cut tube. In otherembodiments, more than one tube may be used to form each of the shafts564, 576 and 578. For example, FIG. 24 illustrates proximal shaft 368comprising two tubes connected by welding such as described above.

Referring again to FIG. 24A, distal contrast media preferably can beinjected through a lumen 388 in the shafts 576 and 578 for determiningthe placement of the implant 100. This lumen 388 may be in fluidcommunication with distal injection port 414, shown in FIG. 22. Thedistal shaft 370 preferably comprises a mating surface 390 and aradiopaque marker 360, such as described above. In one embodiment, themating surface 390 is a threaded surface. The distal shaft 370preferably is releasably coupled to the implant 100, such as describedabove.

FIG. 25 illustrates an embodiment of a puzzle lock profile 600 that maybe used with any of the embodiments of the implant delivery system 50described herein in order to increase flexibility. As discussed above,some of the embodiments deliver an implant 100 to the LAA 10 in anorientation and under a loading condition that approximates the finalreleased state of the implant 100. This reduces bias and moment armsthat can cause the implant 100 to deform, move, jump, or changeorientation when the implant 100 is released from the implant deliverysystem 50. Component rigidity and off-axis loading can contribute tothese undesirable effects. An elongate tube having a strong, flexible,cut wall pattern such as the puzzle lock profile 600 can improve systemflexibility and reduce unwanted loading conditions.

FIGS. 25A-25C illustrate a puzzle lock profile 600 in accordance with anembodiment. The puzzle lock profile 600 can be used to create highlyflexible materials such as tubing with push, pull, and torquecapabilities. The puzzle lock profile 600 can be used to transmit axialloads and rotational torque loads while minimizing bending loads throughits flexibility. As illustrated, one embodiment of the puzzle lockprofile 600 comprises a cut through a tube or a layer of material usinga laser or some other similar manufacturing means known in the art.Referring to FIG. 25B, illustrated is a tube 605 with a longitudinalaxis 610, a diametric axis 620, and a puzzle lock profile 600 cut intoit. The tube 605 can be any tube or shaft discussed herein. Thelongitudinal axis 610 runs along the general axis in the lumen of a tubeor through the center of a solid tube when that tube is straight. Thediametric axis 620 lies in a plane that is perpendicular to thelongitudinal axis 610 and runs along a diameter of the tube 605.

In some embodiments, a cut 635 may start at either the proximal ordistal end of the tube 605. In other embodiments, a cut 635 may start atan offset length 630 from an end of a tube 605. The offset 630 mayprovide structural support to the ends of the tube or may represent anuncut tubing length prior to a puzzle cut region in a tube. Acorresponding offset 630 may exist at the other end of the tube 605, andin some embodiments there may be a plurality of regions in a tube 605,alternating between puzzle lock profile 600 regions and uncut tubing oroffset 630 regions.

Referring to FIG. 25C, a puzzle lock profile 600 is presented in closeup of a tube 605. FIG. 25C may also be considered a view of a tube 605that has been sliced longitudinally and spread into a flat planarsurface. In this view, a cut 635 can have a cut axis 640 which runsalong the length of the cut 635. As illustrated, the weaving cut 635follows a repeating pattern that is symmetric around the cut axis 640.In one embodiment a tube 605 has a number of generally parallel cut axes640, 650, 660, and 670. Additional cut axes may continue along a lengthof the tube 605 (not illustrated). In one embodiment, cut axes 640, 650,660, and 670 may be parts of a single continuous cut that traversesexternal surface of a tube 605, similar to a spiral. In anotherembodiment, cut axis 640 and cut axis 650 may be two parallel cut axesthat are offset from each other, creating two interlaced parallel spiralcuts along the tube 605. In one embodiment, the two spiral cuts start180 degrees from each other in a plane perpendicular to the longitudinalaxis 610 of the tube 605 to create two symmetric spiral cuts and twohelical tube surfaces. The two starting points may be located on thediametric axis 620 at intersection points with the external surface ofthe tube 605. In this embodiment, a first cut 635 moves along a cut axis640 which is contiguous with cut axis 660, and a second cut 636 iscontiguous with cut 670. In other embodiments, there may be two, three,four, or a plurality of cuts, such as cut 635, cut 636, cut 637 and cut638, that create parallel spiral cuts along the tube 605 with cut axes640, 650, 660, and 670, respectively, which can create either symmetricor non-symmetric spiral cuts and helical tube surfaces along the tube605.

Referring to FIG. 25C, illustrated is an embodiment of a puzzle lockprofile 600 with a single cut 635 that extends along cut axes 640, 650,660, and 670 each time the cut 635 wraps around the outer circumferenceof a tube 605. The cut 635 extends generally around the circumference ofthe tube 605 and follows a continuous repeating pattern which isinclined at a slight angle .alpha. from a diametric axis 620 to alongitudinal axis 610 of the tube 605. Each of the cut axes 640, 650,660, and 670 are parallel to each other with a planar cut axis that canbe drawn along the general direction of the cut 635. In one embodiment,a cut 635 is oriented to follow a cut axis 640 with an angle .alpha. ofzero degrees, the cut axis 640 being parallel to the diametric axis 620and perpendicular to the longitudinal axis 610 of the tube 605,resulting in a cut that would traverse the circumference of the tube 605and return to the same location as its starting point, thereby creatinga series of interlocked rings with multiple cuts. In another embodiment,angle .alpha. may be anywhere in a range of 0 to 90 degrees, where insome embodiments angle .alpha. may be about 1, 2, 3, 4, 5, 6, 7, 8, 9,10, 15, 20, 25, 30, 35, 40, 45, 50, 60, 65, 70, 75, 80, 85, or 90degrees. In the illustrated embodiment in FIG. 25C, angle .alpha. is inthe range of about 5-7 degrees.

Along a given cut axis 640, the cut 635 may run along a pattern thatalternates on either side of the cut axis 640 and that runs parallel tothe cut axis 640 at a distance 642 and a distance 643. In someembodiments, distance 642 equals distance 643. As a cut 635 alternateson either side of the cut axis 640 the pattern cuts a length 646 along acut axis 640 when the cut 635 is on the distance 643 from the cut axis640, and a length 647 along a cut axis 640 when the cut 635 is on thedistance 642 from the cut axis 640. In some embodiments, length 646equals length 647. As a cut 635 runs along a pattern at a distance 643,it enters a bend toward the cut axis 640. The bend has a radius 644which is on the order of half of the distance 643. As the cut 635approaches the cut axis 640 the bend reaches an inflection point andchanges direction, creating a bend with a radius 645 which is on theorder of half of the distance 642. In some embodiments, radius 644equals radius 645. These bends create a set of interlocking projectionsthat keep the tube engaged to transmit axial loads and rotational loads,about the longitudinal axis 610 while providing flexibility in the tube605 to reduce bending moments.

The dimensions of a cut 635 with respect to a cut axis 640 depends onthe desired push, pull, and torque characteristics of a given tube 605,and may further depend on tube 605 thickness, diameter, length, andmaterial. In some embodiments, the tube 605 is made of metal, stainlesssteel, hypodermic materials, nickel titanium, plastic, polymers, silver,or radiopaque visualization materials. Angles and lengths and variousother dimensions depend on the number of parallel cuts that may bedesired as well. Embodiments of the puzzle lock profile 600, asillustrated in FIGS. 25 and 25A-25C, may be used in the material of animplant actuation shaft 334, a lock tube 234, a catheter body 302, aretrieval catheter 502, a transeptal sheath 520, a catheter system 300,a retrieval catheter system 500, or any component of an implant deliverysystem 50, as discussed herein. The puzzle-interlocking features 338illustrated provide super flexibility of the various tubes whilemaintaining push, pull and torque transmission capabilities. Any of thepuzzle-interlocking profile 600 tubes can be covered with a thinsilicone tubing to provide a seal over the interlocking portions of thetube to allow for transport of contrast or other fluids within the lumenof the tubes. In some embodiments, portions of tubes (such as a flexiblecore section 372 or a flexible segment 384 as illustrated in FIG. 24)which require greater flexibility can use the puzzle lock profile 600which are attachable to other embodiments of the respective tube. Inother embodiments, the entire tube or component can be constructed usinga puzzle lock profile 600.

In one embodiment, a puzzle lock profile 600 is incorporated into animplant actuation shaft 334. Previous embodiments of implant actuationshafts 334 have been described in terms of an axial moveable core 304and a torque rod 340, as discussed above relating to at least FIGS.17-21. The implant actuation shaft 334 is generally a tubular structurefor imparting a distal force on the distal end 102 of the implant 100.In various embodiments, the implant actuation shaft 334 can be ahypodermic or a metallic tube. In addition, the implant actuation shaft334 can be cut (e.g., laser cut) to have a spiral or puzzle-lock wallprofile 600. One embodiment of a puzzle lock profile 600 is shown inFIG. 25. A spiral cut has little resistance to bending, is capable ofapplying limited compression and can be torqued in one direction. Thepuzzle-lock profile 600 cut has these same properties but is alsocapable of applying tension and torque in both directions. The puzzlelock 338 is generally screwed in and out of the catheter system 300 inboth clockwise and counter-clockwise directions. Since both cutsgenerally are not able to apply bending moment, they are bothadvantageously very flexible. Embodiments of puzzle-lock tubes aredisclosed in U.S. Pat. No. 6,273,876, filed Nov. 3, 1998, which isincorporated by reference herein.

Referring back to FIGS. 21A-21C, there is illustrated an embodiment of aflexible sock 392, such as a metallic mesh sock 392 (e.g., made fromnickel titanium, or NITINOL), which partially covers at least a portionof an implant actuation shaft 334 and a slide tube 394. The implantactuation shaft 334 works with the sock 392 to collapse the implant. Asdiscussed above, the memory metal properties of the implant 100 causeits natural state to be open, or radially expanded to anexpanded-diameter configuration. Distal force is applied to override thenatural state and place the implant 100 in tension in order to reducethe implant 100 to its reduced-diameter configuration. A small momentarm associated or combined with the distal force can cause the deliverycatheter 302 to bend. This in turn can cause the implant 100 to shiftand change its spatial orientation, depending upon the amount of forceand/or the amount the implant 100 is collapsed. A concentric,360.degree. application of tension concentric to the compression forcedelivering implant actuation shaft 334 helps achieve non-biasedexpansion of the implant 100. The tension member in the form of a sock392 avoids applying bending moment, as previously discussed. It alsoavoids applying compression. In order for the left atrial appendage (notillustrated here) to naturally assert its influence on the implant 100and for the implant 100 to be properly seated within the left atrialappendage, once the tension has been released, it is advantageous if noadditional expansion loads are transmitted from the delivery catheter302 to the implant 100. If there were, the delivery catheter 302 couldfalsely bias the implant 100 into an exaggerated or over-expandedexpanded state, which would not represent the final release conditions.In such cases the expansion force of the implant 100 could override thecompression forces provided by the left atrial appendage.

The sock 392, which can be a braided, multi-stranded nickel titaniumtube, is preferably used to help achieve concentric application oftension to the implant 100. Prototypes have shown tensile forcesexceeding two times those used to collapse the implant 100; no bendingresistance; and no compression load transfer over the first 50% of axialstrain (e.g., the sock 392 flexibly collapses to a point, as illustratedin FIG. 21C). The sock 392 can provide tension forces to the proximalend 104 of the implant 100 via the disconnect flex fingers 238 describedabove. The sock 392 can be attached to the delivery catheter 302 anddisconnect mount 236 using any method known to those of skill in theart, including adhesive, welds, bonds, mechanical links, pins, etc. Inone embodiment, LOCTITE adhesive is used to bond the proximal end of thesock 392 to the distal end of the delivery catheter 302. In otherembodiments, the sock 392 is trapped with a laser weld or swaged ring.The sock 392 can also be re-flowed directly into the delivery catheter302 outer lumen or it can be an extension of a braid that can beprovided in the delivery catheter 302. The ability of the sock 392 to“spring back,” or return to its initial state without taking a permanentset helps maintain consistent expansion and collapse properties duringthe implant 100 deployment and recapture process. The super-elasticproperties of NITINOL are well-suited for use as the sock 392. Inaddition, a stainless steel braid will take a set and create compressionbias as well. In one embodiment, the sock 392 may use aspects of apuzzle lock profile 600 as described above.

In some embodiments, a slide tube 394 is provided inside the sock 392and outside an implant actuation shaft 334. The slide tube 394 may beused to prevent the sock 392 from binding on a implant actuation shaft334 or act as a stop in limiting axial motion of the implant actuationshaft 334. The slide tube 394 may slide freely with respect to theimplant actuation shaft 334 or the collar 394 may be attached to theimplant actuation shaft 334 in any number of ways know to the art. Inone embodiment, the slide tube 394 may be an integral part of theimplant actuation shaft 334. As shown in FIGS. 21A-21C, an embodiment ofan implant delivery system 50 includes a slide tube 394. A handle (notillustrated here) provides proximal tension, a sock 392 necks down ontothe slide tube 394 and pulls a proximal end 104 of an implant 100 awayfrom its distal end 102. The distal end 102 is held “stationary” by animplant actuation shaft 334. As the sock 392 pulls the proximal end 104proximally with respect to the distal end 102, the implant 100 isreduced in diameter. As the tension on the proximal end 104 is releasedthe proximal end 104 moves distally towards the distal end 102, and theimplant's diameter expands. A control on the handle controls tension onthe proximal end 104.

B. Configurations and Methods of Use of an Implant Delivery System

Referring to FIG. 6, illustrated is an embodiment of an implant deliverysystem 50. The system and method allows for access and assessment of theLAA 10. In one embodiment, a guidewire (not shown) is used to access thesuperior vena cava through groin access. A transseptal sheath 520 isadvanced over the guidewire and into the superior vena cava. Theguidewire is removed and replaced with a transseptal needle (not shown).The transseptal sheath 520 preferably is retracted inferiorly so that abend in the transseptal sheath directs the distal tip of the transseptalsheath toward the fossa ovalis. The needle is advanced to puncture thefossa ovalis. The transseptal sheath 520 is advanced to establish accessto the LAA 10 and the needle is retracted. Further details or disclosureare provided above and in copending U.S. patent application Ser. No.09/435,562 and U.S. Pat. No. 7,044,134, issued May 16, 2006, theentireties of which are hereby incorporated by reference.

After preparing a transseptal sheath 520 for LAA 10 access, the size ofthe neck diameter and morphology of the LAA 10 preferably is determinedby advancing the transseptal sheath 520 to the distal portion of the LAA10 and injecting contrast media to obtain an initial left atrialappendogram. The neck diameter preferably is measured approximately 5 mmin from the ostium of the LAA 10 at end diastole.

Referring to FIG. 22, illustrated is an embodiment of a system andmethod that allows for selection and preparation of a deployment system50. A deployment system 50 preferably comprises an implant 100 of anappropriate size for placement in a patient. Initially, the implant 100preferably is in an expanded configuration, with an implant release andrecapture mechanism 200 engaging the implant 100, as described above.The recapture sheath 522 preferably is positioned so it covers andsupports the flexible segment 384 of the delivery system 50, wherein theflexible catheter section 362 of deployment catheter 302 and flexiblecore section 372 of axially moveable core 304 are aligned. TheTouhy-Borst valve 530 preferably is tightened over the deploymentcatheter 302 to prevent relative movement between recapture sheath 522and deployment catheter 302. The loading collar 323 and peel-away sheath314 preferably are positioned so they are at the base of the recaptureflares 510, proximal thereto.

In one embodiment, the delivery system 50 is loaded by rotating thecontrol knob 408 counterclockwise until the implant 100 is fullycollapsed. Preferably, at least a portion of the control line 312 iscoupled with the control knob 408 such that rotation of the control knob408 retracts at least a portion of the control line 312. In anembodiment, the rotation of the control knob 408 is in thecounterclockwise direction to retract at least a portion of the controlline 312. Retraction of the control line 312 preferably places tensionon the proximal hub 104 of the implant 100, because a portion of thecontrol line 312 preferably is coupled with the proximal hub 104 by apin 146. While the distal portion of the axially moveable core 304applies a distal force to distal hub 108 of the implant 100, tension inthe control line 312 preferably causes the proximal hub 104 of theimplant 100 to move proximally relative the axially moveable core 304,thereby collapsing the implant 100.

In another embodiment, the delivery system 50 is loaded with an implant100 connected to an implant release and recapture mechanism 200, whichis connected to a catheter system 300, which is connected to adeployment handle 400. A disconnect mount interface 180 on the proximalend 104 of the implant 100 is connected to a disconnect mount 236 on acatheter system 300 which can provide releasable concentric loading tothe implant 100 as described above. In one embodiment, the concentricloading is concentric tension. In one embodiment the concentric loadingis provided by a disconnect mount interface 180 with a finger interface182 which interacts with a flexible finger 238 on the disconnect mount236. Embodiments of the finger interface 182 may be in the form of aprotruding finger, an interlocking feature, a groove, a slot, a window,or other similar features for releasably holding a disconnect mount 236flexible finger 238. In one embodiment the flexible finger 238 isengaged with the finger interface 182 and a lock tube 234 is slid intoplace to secure the engagement between the flexible finger 238 isengaged with the finger interface 182. In some embodiments, the locktube 234 may be rotated to threadably engage with a catheter 302 to lockin place. In other embodiments no lock tube 234 is necessary.

An implant actuation shaft 334 may be extended distally through thecatheter 302 into the implant 100 to radially-reduce the implant 100 byplacing the implant 100 in tension. The implant actuation shaft 334 maybe advanced distally by axial sliding, rotational engagement with athreaded surface 336, or a combination of both. In one embodiment, theimplant actuation shaft 334 has a threaded portion 336 that threadablyengages with a hub 236 to lock the implant 100 in a radially reducedconfiguration, as described above. In this embodiment, the implant 100may be loaded by sliding the implant actuation shaft 334 distally untilits threaded portion 336 comes into contact the hub 236, and thenrotating the control knob 408 counterclockwise to threadably engage thethreaded portion 336 and the hub 236 until the implant 100 is fullycollapsed.

The diameter of the implant 100 preferably is reduced to approximately⅓.sup.rd or less of its original diameter when collapsed. The loadingcollar 323 and peel-away sheath 314 are then advanced distally over theflares 510 and implant 100 until the distal tip of the implant 100 isaligned with the distal end of the peel-away sheath 314 and the distalend of the loading collar is about 1.5 cm from the distal tip of theimplant 100. At this point, the flares 510 partially cover the implant.The loading collar 323 preferably is removed and discarded.

With the implant 100 partially within the recapture sheath 522 andretracted within the peel-away sheath 314, the entire system preferablyis flushed with sterile heparinized saline after attaching stopcocks tothe recapture sheath injection port 529, the proximal injection port 412and distal injection port 414 of the delivery system 50. The recapturesheath 522 and the Touhy-Borst valve 530 are first thoroughly flushedthrough port 529. Then the distal injection port 414 and the proximalinjection port 412 of the deployment handle 400 are preferably flushedthrough. The distal injection port 414 is in fluid communication withlumen 388 of axially moveable core 304 (as illustrated in FIG. 24A), andproximal injection port 412 is in fluid communication with injectionlumens 332 of multilumen shaft 326. The transseptal sheath 520 placementpreferably is reconfirmed using fluoroscopy and contrast mediainjection.

The delivery system 50, as described above, with implant 100 insertedtherein, preferably is then inserted into the proximal end of atransseptal sheath 520 (as shown in FIG. 6). To avoid introducing airinto the transseptal sheath 520 during insertion of the delivery system50, a continual, slow flush of sterile heparinized saline preferably isapplied through the proximal injection port 412 of the deployment handle400 to the distal end of the deployment catheter 302 until the tip ofthe peel-away sheath 314 has been inserted into, and stops in, thehemostatic valve of the transseptal sheath 520. Preferably, the distaltip of the peel-away sheath 314 is inserted approximately 5 mm relativeto the proximal end of the transseptal sheath 520.

Under fluoroscopy, the recapture sheath 522 and deployment catheter 302preferably are advanced, relative to the peel-away sheath 314,approximately 20-30 cm from the proximal end of the transseptal sheath520, and the system 50 preferably is evaluated for trapped air. Thepeel-away sheath 314 is preferably not advanced into the transseptalsheath 520 due to a hemostasis valve (not illustrated) on thetransseptal sheath 520 blocking its passage. If air is present in thesystem 50, it may be removed by aspirating through the distal injectionport 414, recapture sheath injection port 529, or proximal injectionport 412. If air cannot be aspirated, the deployment catheter 302 andrecapture sheath 522 preferably are moved proximally and the deliverysystem 50 preferably is removed from the transseptal sheath 520. All airpreferably is aspirated and the flushing/introduction procedurepreferably is repeated.

The peel-away sheath 314 preferably is manually slid proximally to theproximal end 524 of the recapture sheath 522. The Touhy-Borst valve 530preferably is loosened and the deployment catheter 302 preferably isadvanced distally relative to the recapture sheath 522 until thedeployment handle 400 is within about 2 cm of the Touhy-Borst valve 530of the recapture sheath 522. This causes the implant 100 to be advanceddistally within the transseptal sheath 520 such that the recapturesheath 522 no longer covers the implant 100 or the flexible section 558.The Touhy-Borst valve 530 preferably is tightened to secure thedeployment catheter 302 to fix relative movement between the deploymentcatheter 302 and recapture sheath 522.

Under fluoroscopy, the implant 100 preferably is advanced to the tip ofthe transseptal sheath 520 by distal movement of the delivery catheter302. The distal hub 108 of implant 100 preferably is aligned with atransseptal sheath tip radiopaque marker 521 (see FIG. 6). Underfluoroscopy, the sheath 520 positioning within the LAA 10 preferably isconfirmed with a distal contrast media injection.

The position of the implant 100 preferably is maintained by holding thedeployment handle 400 stable. The transseptal sheath 520 preferably iswithdrawn proximally until its tip radiopaque marker 521 is aligned withthe distal end of the deployment catheter flexible segment 384. In someembodiments, the transseptal sheath 520 is withdrawn proximally untilits tip radiopaque marker 521 is aligned with the distal end of the meshsock 392. In other embodiments, the transseptal sheath 520 is withdrawnproximally until its tip radiopaque marker 521 is aligned with theproximal end of the mesh sock 392, or at a location between the proximaland distal ends of the mesh sock 392. This preferably exposes theimplant 100.

In one embodiment, under fluoroscopy, the implant 100 preferably isexpanded by rotating the control knob 408 clockwise until it stops.Rotating the control knob 408 preferably releases tension on the controlline 312, preferably allowing the implant 100 to expand. The implant 100preferably is self-expanding. After expansion, any tension on the LAA 10preferably is removed by carefully retracting the deployment handle 400under fluoroscopy until the radiopaque marker 360 (see FIG. 24) on theaxially movable core 304 moves proximally approximately 1-2 mm in theguide tube 130 (see FIG. 11). In an embodiment, the position of theimplant 100 relative the LAA 10 preferably is not altered because theaxially movable core 304 preferably is coupled with an axially decoupledimplant release and recapture mechanism 200, as is shown in anembodiment illustrated in FIGS. 16A and 16B, which allows for relativemovement between the implant 100 and the axially movable core 304. Theimplant release and recapture mechanism 200 preferably allows for thedistal portion of the axially movable core 304 to be slightly retractedproximally from the distal end 102 of the implant 100, thereby removingany axial tension that may be acting on the implant 100 through theaxially movable core 304. The axial moveable core 304 radiopaque marker360 preferably is about 1-2 mm proximal from the implant 100 distal end102, and the transseptal sheath 520 tip preferably is about 2-3 mmproximal from the implant proximal end 104, thereby indicating a neutralposition.

In another embodiment, the delivery system 50 comprises an implant 100connected to an implant release and recapture mechanism 200, which isconnected to a catheter system 300, which is connected to a deploymenthandle 400. A disconnect mount interface 180 on the proximal end 104 ofthe implant 100 is connected to a disconnect mount 236 on a cathetersystem 300 which provides releasable concentric loading to the implant100 as described above. In one embodiment, the concentric loading isconcentric tension. In one embodiment the concentric loading is providedby a disconnect mount interface 180 with a finger interface 182 whichinteracts with a flexible finger 238 on the disconnect mount 236.

As discussed above, in some embodiments the order of the following stepsmay be accomplished in the following sequence, or in reverse sequence,or in a combination of repeated steps in order to have the implant 100expand and release an implant 100 in a distal, proximal, or relativelyaxially-stationary direction.

In one embodiment, the implant actuation shaft 334 may be retractedproximally through the catheter 302 through the implant 100 toradially-expand the implant 100 by removing the tensile load from distalend 102 of the implant 100. The implant actuation shaft 334 may beretracted proximally by axial sliding, rotational engagement with athreaded surface 336, or a combination of both. In one embodiment, theimplant actuation shaft 334 has a threaded portion 336 that threadablyengages with a hub 236 to lock the implant 100 in a radially reducedconfiguration, as described above. In this embodiment, the implant 100may be unloaded rotating the control knob 408 until the hub 236 andimplant actuation shaft 334 threaded portion 336 detach, and by slidingthe implant actuation shaft 334 proximally. If the implant actuationshaft 334 is moved proximally and the proximal end 104 of the implant100 remains relatively stationary with respect to the catheter body 302,the implant 100 will expand within the LAA 10 in a generally proximaldirection, as described above.

In one embodiment a disconnect mount interface 180 on the proximal end104 of the implant 100 is connected to a disconnect mount 236 on acatheter system 300 which can provide releasable concentric loading tothe implant 100 as described above. In one embodiment, the concentricloading is concentric tension. In one embodiment the concentric loadingis provided by a disconnect mount interface 180 with a finger interface182 which interacts with a flexible finger 238 on the disconnect mount236. The flexible finger 238 is engaged with the finger interface 182and a lock tube 234 secures the engagement between the flexible finger238 and the finger interface 182. In one embodiment, the implant 100 maybe expanded by allowing the catheter 302 to advance distally while theimplant actuation shaft 334 remains stationary at the distal end 102 ofthe implant 100 as is illustrated in FIGS. 18A and 18B. In anotherembodiment, a mesh sock 392 in a compressed state may be released toallow the proximal end 104 of the implant 100 to move distally while theimplant actuation shaft 334 remains stationary at the distal end 102 ofthe implant 100. In another embodiment, the implant 100 may be expandedby removing the lock tube 234 from the flexible finger 238 and fingerinterface 182. In some embodiments, the lock tube 234 may be rotated tothreadably disengage from a catheter 302 to unlock the lock tube 234. Inother embodiments no lock tube 234 is necessary. When the implantactuation shaft 334 remains extended and attached to the proximal end104 of the implant 100 and the fingers 238 are released from the fingerinterfaces 182, the implant 100 will expand within the LAA 10 in agenerally distal direction, as described above.

The implant 100 preferably is self-expanding. After expansion, anytension on the LAA 10 preferably is removed by carefully retracting thedeployment handle 400 under fluoroscopy until the radiopaque marker 360(see FIG. 24) on the axially movable core 304 moves proximallyapproximately 1-2 mm in the guide tube 130 (see FIG. 11). In anembodiment, the position of the implant 100 relative the LAA 10preferably is not altered because the implant actuation shaft 334preferably is coupled with an axially decoupled implant release andrecapture mechanism 200, as is shown in an embodiment illustrated inFIGS. 16A and 16B, which allows for relative movement between theimplant 100 and the implant actuation shaft 334. The implant release andrecapture mechanism 200 preferably allows for the distal portion of theaxially movable core 304 to be slightly retracted proximally from thedistal end 102 of the implant 100, thereby removing any axial tensionthat may be acting on the implant 100 through the axially movable core304. The axial moveable core 304 radiopaque marker 360 preferably isabout 1-2 mm proximal from the implant 100 distal end 102, and thetransseptal sheath 520 tip preferably is about 2-3 mm proximal from theimplant proximal end 104, thereby indicating a neutral position.

Under fluoroscopy, the expanded diameter (O in FIG. 6) of the implant100 preferably is measured in at least two views to assess the positionof the implant within the LAA 10. The measured implant diameter Opreferably is compared to the maximum expanded diameter.

Preferably, the labeled proximal 412 and distal injection ports 414, ofthe deployment handle 400 shown in FIG. 22, correlate with the proximaland distal contrast media injections. The proximal contrast mediainjections are delivered through the delivery catheter lumen 332 to alocation proximal to the implant 100. The distal contrast mediainjections are delivered through the axially movable core 304 to alocation distal to the implant 100. Proximal contrast media injectionspreferably are completed in two views. If the injection rate isinsufficient, the recapture sheath injection port 529 may be usedindependently or in conjunction with the proximal injection port 412 todeliver fluid to a location proximal to the implant 100.

If satisfactory results are seen, any transverse tension on the LAA 10preferably is released by exposing the flexible segment 384 of thedelivery system 50. The flexible catheter section 362 and the flexiblecore section 372 preferably are linearly co-located to cooperate as theflexible segment 384 of the delivery system 50. This preferably isaccomplished by retracting the transseptal sheath 520 proximallyapproximately 2 cm to expose the flexible segment. By exposing theflexible segment 384, the flexible segment 384 preferably will flex toallow the implant 100 to sit within the LAA 10 free from transverseforces that may be created, for example, by contractions of the heartacting against the transseptal sheath 520 or deployment catheter 302.Once the flexible segment 384 is exposed, distal contrast mediainjections preferably are completed in at least two views to verifyproper positioning of the implant 100. A flush of saline preferably isused as needed between injections to clear the contrast media from theLAA 10. Following the contrast media injections, the transseptal sheath520 preferably is advanced distally to cover the flexible segment 384.

In another embodiment, any transverse tension on the LAA 10 preferablyis released by a mesh sock 392 and a proximal retraction of an implantactuation shaft 334.

If implant 100 position or results are sub-optimal, the implant 100preferably may be collapsed and repositioned in the LAA 10. In someembodiments, the implant 100 is still attached to an implant release andrecapture mechanism 200 and the radial-reduction of the implant 100 isaccomplished by the actuation of the implant actuation shaft 334. Inother embodiments, the implant 100 must be reattached to the implantrelease and recapture mechanism 200 before the radial-reduction of theimplant 100 can be accomplished by the actuation of the implantactuation shaft 334. To collapse and reposition an implant 100 in oneembodiment under fluoroscopy, the deployment handle 400 preferably isadvanced distally to place the radiopaque marker 360 of the axiallymoveable core 304 at the distal hub 108 of the implant 100. The distalend of the transseptal sheath 520 preferably is aligned with the distalend of the flexible segment 384. The control knob 408 preferably isrotated until the implant 100 has been collapsed to approximately⅓.sup.rd or less of its expanded diameter. The control knob 408preferably acts on the control line 312 to place tension on the proximalhub 104 of the implant 100, pulling the proximal hub 104 of the implant100 proximally relative the distal hub 108 of the implant 100 tocollapse the implant 100. The implant 100 preferably can be repositionedand re-expanded. In another embodiment, an implant actuation shaft 334is reintroduced or advanced distally within a radially-enlarged implant100 and advanced to the distal end 102 of the implant 100.

The stability of the implant 100 preferably is verified in severalviews. Stability tests preferably are preformed in the following manner.A contrast media filled syringe preferably is connected to the distalinjection port 414 of the deployment handle 400. Under fluoroscopy, atleast about a 10 mm gap between the tip of the transseptal sheath 520and the proximal hub 110 of the implant 100 is preferably confirmed. Thestability of the implant 100 in the LAA 10 preferably is evaluated usingfluoroscopy and echocardiography. The recapture sheath Touhy-Borst valve530 preferably is loosened. Then the deployment handle 400 preferably isalternately retracted and advanced about 5-10 mm while maintaining theposition of the transseptal sheath 520 and simultaneously injectingcontrast media through the distal injection port 414. This tests howwell the implant is held within the LAA 10. If the implant stabilitytests are unacceptable, the implant 100 preferably may be collapsed andrepositioned as described above. If repositioning the implant 100 doesnot achieve an acceptable result, the implant 100 preferably may becollapsed and recaptured as described further below.

The implant 100 preferably meets the following acceptance criteria,associated with the assessment techniques listed below, prior to beingreleased. The assessment techniques to be evaluated preferablyinclude 1) residual compression; 2) implant location; 3) anchorengagement; 4) seal quality; and 5) stability. For residual compression,the implant diameter O, as measured by fluoroscopic imaging, preferablyis less than the maximum expanded diameter of the implant 100. Forimplant location, the proximal sealing surface of the implant 100preferably is positioned between the LAA 10 ostium and sources ofthrombus formation (pectinates, secondary lobes, etc.) (preferablyimaged in at least two views). For anchor engagement, the implant frame101 preferably is positioned within the LAA 10 so as to completelyengage a middle row of anchors 118 in an LAA 10 wall (preferably imagedin at least two views). For seal quality, the contrast injectionspreferably show leakage rated no worse than mild (preferably defined asa flow of contrast media, well defined, and filling one-third of the LAA10 during a proximal injection over a period of up to about fiveventricular beats, preferably imaged in at least two views). Forstability, there preferably is no migration or movement of the implant100 relative to the LAA 10 wall as a result of the Stability Test.

If implant 100 recapture is necessary, because a different size implant100 is necessary or desired, or if acceptable positioning or sealingcannot be achieved, the implant 100 preferably is fully collapsed asdescribed above. In one embodiment, once the implant 100 is collapsed,the locking collar 315 of the peel away sheath 314 preferably isunlocked. The peel-away portion 524 of the peel-away sheath 314preferably is split up to the reinforced section 317 and removed. Thereinforced section 317 of the peel-away sheath 314 preferably is slidproximally to the hub of the recapture sheath 522. The Touhy-Borst valve530 on the proximal end of the recapture sheath 522 preferably isslightly loosened to allow smooth movement of the sheath 522 overdeployment catheter 302 without allowing air to enter past theTouhy-Borst valve 530 seal. By removing the peel-away portion 524 ofpeel-away sheath 314, the recapture sheath 522 can now be advancedfurther distally relative to the transseptal sheath 520.

While holding the deployment catheter 302 and transseptal sheath 520 inplace, the recapture sheath 522 preferably is advanced distally into thetransseptal sheath 520 until a half marker band 536 on the recapturesheath 522 is aligned with a full marker band 521 on the transseptalsheath 520. This preferably exposes the recapture flares 510 outside thetransseptal sheath.

The collapsed implant 100 preferably is retracted into the recapturesheath 522 by simultaneously pulling the deployment handle 400 andmaintaining the position of the recapture sheath 522 until approximatelyhalf the implant 100 is seated in the recapture sheath 522. TheTouhy-Borst valve 530 on the recapture sheath 522 preferably istightened over the deployment catheter 302. The recapture sheath 522 andimplant 100 preferably are retracted into the transseptal sheath 520 bypulling on the recapture sheath 522 while maintaining the position ofthe transseptal sheath 520, preferably maintaining left atrial access.The recapture flares 510 of the recapture sheath 522 preferably cover atleast some of the anchor elements 195 on the implant 100 as the implantis retracted proximally into the transseptal sheath 520. Further detailsare described above with respect to FIGS. 15C-15E.

If the implant's position and function are acceptable, and implantrecapture is not necessary, the implant 100 preferably is released fromthe delivery system 50. In one embodiment, under fluoroscopy, thetransseptal sheath 520 is advanced to the proximal hub 104 of theimplant 100 for support. The release knob 410 on the proximal end of thedeployment handle 400 preferably is rotated to release the implant 100.Rotating the release knob 410 preferably causes a threaded portion ofthe distal shaft 344 of the axially movable core 304 to rotate withrespect to the threaded aperture 346 such that the threaded portion ofthe distal shaft 344 preferably is decoupled from the implant 100. Underfluoroscopy, after the axially movable core 304 is decoupled from theimplant 100, the release knob 410 preferably is refracted until thedistal end 310 of the axially movable core 304 is at least about 2 cmwithin the transseptal sheath 520.

In one embodiment a disconnect mount interface 180 on the proximal end104 of the implant 100 is connected to a disconnect mount 236 on acatheter system 300 which can provide releasable concentric loading tothe implant 100 as described above. In one embodiment, the concentricloading is concentric tension. In one embodiment the concentric loadingis provided by a disconnect mount interface 180 with a finger interface182 which interacts with a flexible finger 238 on the disconnect mount236. The flexible finger 238 is engaged with a finger interface 182 anda lock tube 234 secures the engagement between the flexible finger 238and the finger interface 182. Under fluoroscopy, the implant 100 may bedetached by removing the lock tube 234 from the flexible finger 238 andfinger interface 182. In some embodiments, the lock tube 234 may berotated to threadably disengage from a catheter 302 to unlock the locktube 234. In other embodiments no lock tube 234 is necessary. In otherembodiments sufficient proximal retraction of the implant actuationshaft 334 is required in order to release the disconnect mount interface180 from the disconnect mount 236, as described above.

Under fluoroscopy, while assuring that transseptal access is maintained,the delivery system 50 preferably is retracted and removed through thetransseptal sheath 520. Under fluoroscopy, the transseptal sheath 520position preferably is verified to be approximately 1 cm away from theface of the implant 100. Contrast injections, fluoroscopy and/orechocardiography preferably may be used to confirm proper positioningand delivery of the implant 100 and containment of the LAA 10. Thetransseptal sheath 520 preferably is withdrawn.

Throughout this application the terms implant and occlusion device havebeen used. One of ordinary skill in the art will appreciate that all ofthe disclosures herein are applicable to a wide variety of structuresthat include both implants that may or may not also be occlusiondevices. Routine experimentation will demonstrate those limitedcircumstances under which certain disclosures and combinations thereofare not beneficial.

Further details regarding left atrial appendages devices and relatedmethods are disclosed in U.S. Pat. No. 6,152,144, titled “Method andDevice for Left Atrial Appendage Occlusion,” filed Nov. 6, 1998, U.S.patent application Ser. No. 09/435,562, filed Nov. 8, 1999, U.S. patentapplication Ser. No. 10/033,371, titled “Method and Device for LeftAtrial Appendage Occlusion,” filed Oct. 19, 2001, and U.S. applicationSer. No. 10/642,384, filed Aug. 15, 2003, titled “System and Method forDelivering a Left Atrial Appendage Containment Device,” published asU.S. Publication No. 2005/0038470. The entirety of each of these ishereby incorporated by reference.

While particular forms of the invention have been described, it will beapparent that various modifications can be made without departing fromthe spirit and scope of the invention. Accordingly, it is not intendedthat the invention be limited, except as by the appended claims.

1. An implant delivery system, comprising: an implantable devicecomprising a plurality of supports extending between a proximal end anda distal end, the supports being moveable between a collapsedconfiguration and an expanded configuration; a proximal guide tube atthe proximal end of the supports extending toward the distal end; and adistal guide tube at the distal end of the supports extending toward theproximal end; wherein the proximal and distal guide tubes aretelescoping and become further engaged as the supports move from thecollapsed to the expanded configuration.